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E34 (1989 - 1995)

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  #1  
Old 04-19-2013, 10:38 PM
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BMR_LVR BMR_LVR is offline
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I need auto electrical help (MB, not BMW but please still help)

Hey guys. I need some help with an automotive electrical problem.

The car: 1991 Mercedes 300E (my sonís)

My sonís car had been doing fine until he sideswiped a tree. The car sustained significant damage to the driverís door, driverís side power mirror, driverís side rear door and the front portion of the driverís side rear quarter panel. The driverís window will only go down a couple of inches. The door can be opened from the inside only. The rear door suffered significant damage as well. I donít know if the window works or not.

Last week, a few days after his accident, his battery went dead. Without consulting me, he bought a new battery. His battery light stayed on. I recommended he take the car to where he bought the battery to have the charging system checked. They told him that his alternator was shot. It was one that I had put on there from a Pull-A-Part about a month ago, so it certainly seemed plausible that it may have failed. He bought a remanufactured alternator from OíReillyís (the cheap $100 unit). I put the alternator on his car last Saturday. After installation, it was showing 13.7 volts at idle. I do know that they only fix whatever is wrong with the alternator and then clean it up and put it back together so itís not as good as a ďrebuiltĒ unit. I thought that with a brand new battery and a remanufactured alternator, all was well.

I was wrong. His battery died again tonight.

I readily admit that automotive electronics (heck, any electronics for that matter) are one of my weakest DIY areas. I have a multimeter and test light.

He was able to be jumped off, drive a few miles and it would die again. I went to where he was. His battery initially showed 11.5 volts, until he tried to start it and it dropped immediately to less than 1 volt. Okay, dead battery, I just didnít know why. I jumped him, but allowed his battery to charge for about 4 minutes prior to jumping it and he was able to make it about 8 miles to his house before his car died again. I did not check the voltage when running when I jumped it because I wanted him to get home ASAP since we were on the side of I-85 and it was getting dark.

Once home, I placed the battery on my charger at 15 amps for about 8 minutes. It showed 12.7 volts. His car cranked right up. The battery tested 13.5 volts when the engine was at idle. It dropped to 13.3 with the headlights on. Now I was really scratching my head.

I disconnected the negative cable from the battery. I put my multimeter to volts and put one probe to the negative post of the battery and the other probe to the negative battery cable. It showed -12.7 volts. Now Iím really scratching my head. I put the test light between the negative battery post and the negative cable. The light came on brightly. I checked with my multimeter again and this time I had +12.7 volts on the negative side. So, I figure that I have voltage on the negative side for some reason. I just donít know why.

I started pulling fuses one at a time and there was no change in the light. I could hear a rhythmical clicking in the power seat relay that corresponded with a dimming of the test light. I pulled the relay. The light stopped pulsing, but I still had voltage on the negative side.

I donít know enough about the electrical system to know what is going on. My hypothesis is that damage to something in the driverís door or passenger door (i.e. window lift motor, power locking actuator, etc.) may have been damaged causing some sort of short.

I need help here. Do any of you that have knowledge of the electrical system of cars know what would cause voltage to be on the negative side of the battery? Is this a short circuit? Would removing the door panels and disconnecting all electrical components in the doors stop this problem?

I appreciate any assistance that you can offer and please keep in mind that I am for the most part a moron when it comes to these electrical problems, so please keep your advice as simple as possible (think ďcar electronics for dummies").

Thanks in advance.
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Steve

Calypso Red 1992 525i with 200K miles

1991 735i - Sold
1992 525i - Sold
1995 325is - Sold
2000 528i - Sold

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  #2  
Old 04-19-2013, 10:53 PM
allenbee allenbee is offline
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Was your son's car dying even while being driven ? Even with a battery that holds no charge, that wont happen unless the alternator is also done.

Is the batt symbol staying on after startup ?
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  #3  
Old 04-20-2013, 12:09 AM
allenbee allenbee is offline
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You are supposed to get 12.7volts when you connect the batt negative post to the multimeter to the negative cable, in series. Whether you see plus or minus depends on how you connect the leads and is not significant for this situation.

You will see the same thing if you did this with the positive terminal (negative terminal and cable connected properly this time of course). You are closing a circuit.

Connect your multimeter in parallell on both ends of each fuse, if you have the metal points showing on each fuse. See if any current over 50mA registers. If it does, that is your current draw probably.

Unlikely that a new battery is defective. Alternator sounds very suspect if the car dies even while being driven. The side swipe may be purely coincidental to the alternator issue, especially if the car has high miles.

Last edited by allenbee; 04-20-2013 at 12:11 AM.
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  #4  
Old 04-20-2013, 03:30 AM
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supertech777 supertech777 is offline
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He is right with the alternator being suspect , the charging system should be 13.8 volts running , but charging the battery for 8 min si not sufficient enoug to get a full charge . Check any loose wiring from the power mirriors that are exposed or grounded somewhere , now with engine off get your test light and remove the negative side cable on the battery and connect the test leads to the negative cable and the negative post of your battery , and fiddle with the side mirror and see if there would be a significant drop to the brightness of the test light . Hope this helps
Ps . Steve as you know there is a lot of electronics on the passenger drivers door . Ie central locking etc etc . And if there are any side marker lights that are damaged on the driver side I would check

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  #5  
Old 04-20-2013, 04:17 AM
allenbee allenbee is offline
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I just realised the first thing you should do is to check for a static current draw with the engine off, since you have several suspects. Hook your multimeter in series with a battery terminal and it's disconnected clamp. Set to 10amps and see if you get a reading, if you don't keep dialing the dmm down until you get a reading. You should get a reading at some point. As long as it's under 50mA you dont have a problem with shorts etc.
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  #6  
Old 04-20-2013, 04:29 AM
allenbee allenbee is offline
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Quote:
Originally Posted by supertech777 View Post
He is right with the alternator being suspect , the charging system should be 13.8 volts running , but charging the battery for 8 min si not sufficient enoug to get a full charge . Check any loose wiring from the power mirriors that are exposed or grounded somewhere , now with engine off get your test light and remove the negative side cable on the battery and connect the test leads to the negative cable and the negative post of your battery , and fiddle with the side mirror and see if there would be a significant drop to the brightness of the test light . Hope this helps
Ps . Steve as you know there is a lot of electronics on the passenger drivers door . Ie central locking etc etc . And if there are any side marker lights that are damaged on the driver side I would check

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Charging system at max electrical load can range from 13.1v onwards to 14v, depending on the car. Zero electrical load would usually be at least 13.5/6v, anything significantly less and you need to schedule an alternator rebuild within 12 months ideally. Not a big deal. As long as its more than 12.7v, the battery is getting recharged. Higher potential difference.

+1 on 8 minutes being way too little to recharge but you probably already knew that and was pressed for time.
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  #7  
Old 04-20-2013, 07:36 AM
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BMR_LVR BMR_LVR is offline
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Okay guys. I just woke up didn't get in bed until 2:00 a.m. - ugh.

Anyway, my coffee is brewing. I will take a closer look at the posts.

Allenbee, please elaborate on what you mean by the term "parrallel". I know that this is opposite of "series", but I don't know what each one means. Remember, I need instructions "for dummies"

Also, yes, the 8 minute charge on the battery charger was just so that I had enough juice to crank the car to check for alternator voltage output.

I'll respond more after some coffee.
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Quote:
Originally Posted by noego View Post
It's Deja Poo - as in, I've heard this **** before.
Steve

Calypso Red 1992 525i with 200K miles

1991 735i - Sold
1992 525i - Sold
1995 325is - Sold
2000 528i - Sold

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  #8  
Old 04-20-2013, 07:42 AM
HipMusic Man HipMusic Man is offline
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If there is a lot of damage to the door the window will not roll down because the dents are in the way. Just as well im sure the wiring between either one of the doors or the quarter panel may have been damaged. They only way to physically look at those would be to take the door panels off and look at the wiring and in the trunk pull back the carpeting and inspect the wiring. if while running the car holds a charge its not the alternator and may not have been in the first place. Also the crash could have moved the wiring around in other parts of the car. If thats the case check to make sure all of the other electrical components are functioning properly. Radio, outelts, climate control, lights, gauges, everything. Also check the fuses while you're at it. Relays you can check with a 9v battery. I have a feeling its in the doors or the panel. Good luck

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  #9  
Old 04-20-2013, 08:21 AM
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BMR_LVR BMR_LVR is offline
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Thanks so much for all of the replies guys. I am hopeful that I will be able to figure this out with your help.

Quote:
Originally Posted by allenbee View Post
Was your son's car dying even while being driven ? Yes Even with a battery that holds no charge, that wont happen unless the alternator is also done. I was under the impression that the car still had to have a decent battery for it to continue to run, even with a good alternator.

Is the batt symbol staying on after startup ? It has not been on since I put in the remanned alternator
Quote:
Originally Posted by allenbee View Post
You are supposed to get 12.7volts when you connect the batt negative post to the multimeter to the negative cable, in series. Whether you see plus or minus depends on how you connect the leads and is not significant for this situation. Now that I have had a little time to think about it, that makes perfect sense.

You will see the same thing if you did this with the positive terminal (negative terminal and cable connected properly this time of course). You are closing a circuit. Got it. Thanks.

Connect your multimeter in parallell on both ends of each fuse, if you have the metal points showing on each fuse. Fortunately, the ends of the fuse on a MD are unbelievably easy to reach. They are exposed, not hidden like in the Bimmer. By in parallel, I assume you mean touching one probe to one end of the fuse and the other probe to the other end of the fuse right? Also, is this to be done with the fuse in or out? Is the car to be running or not?See if any current over 50mA registers. If it does, that is your current draw probably.

Unlikely that a new battery is defective. Alternator sounds very suspect if the car dies even while being driven. The side swipe may be purely coincidental to the alternator issue, especially if the car has high miles. The car has high miles, but it now has a new battery and remanned alternator. This did not occur until the accident, so I do think it is related.
Quote:
Originally Posted by supertech777 View Post
He is right with the alternator being suspect , the charging system should be 13.8 volts running , but charging the battery for 8 min si not sufficient enoug to get a full charge . Understood, but I just wanted to be able to crank the car to check the alternator's voltage output.Check any loose wiring from the power mirriors that are exposed or grounded somewhere , now with engine off get your test light and remove the negative side cable on the battery and connect the test leads to the negative cable and the negative post of your battery , and fiddle with the side mirror and see if there would be a significant drop to the brightness of the test light . Hope this helps
Ps . Steve as you know there is a lot of electronics on the passenger drivers door . Ie central locking etc etc . And if there are any side marker lights that are damaged on the driver side I would check That's my hpothesis too Noel. I think that, after trying to find a problem by checking at each fuse (to firstly and hopefully isolate the problem), I will then likely take the door panels off of the two doors and disconnect everything that is electrical. He doesn't need the components in each door now. I hope that stops the problem.

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Quote:
Originally Posted by allenbee View Post
I just realised the first thing you should do is to check for a static current draw with the engine off, since you have several suspects. Hook your multimeter in series with a battery terminal and it's disconnected clamp. Set to 10amps and see if you get a reading, if you don't keep dialing the dmm down until you get a reading. You should get a reading at some point. As long as it's under 50mA you dont have a problem with shorts etc. Thanks. I think I know what you mean by "in series" here as that is what I was doing last night. Also, in this thougt, I checked the static battery voltage last night before I left. It was 12.6 if I remember correctly. I told my son to NOT put the charger on it overnight. I told him to check the static battery voltage this morning and call me with the results. I would expect there to be almost no drop if there is not a parasitic draw somewhere. If the battery voltage has dropped much, then that would tend to indicate a significant parasitic draw correct?
Quote:
Originally Posted by HipMusic Man View Post
If there is a lot of damage to the door the window will not roll down because the dents are in the way. Yes, but, he can roll the driver's window down about an inch to let his cigarette smoke out - yuck.Just as well im sure the wiring between either one of the doors or the quarter panel may have been damaged. That's my thinking as well. They only way to physically look at those would be to take the door panels off and look at the wiring and in the trunk pull back the carpeting and inspect the wiring. That's my plan, except at stated above, I will likely disconnect all electrical connections in both doors.if while running the car holds a charge its not the alternator and may not have been in the first place. Also the crash could have moved the wiring around in other parts of the car. My thinking here as well. If thats the case check to make sure all of the other electrical components are functioning properly. Radio, outelts, climate control, lights, gauges, everything. Also check the fuses while you're at it. Relays you can check with a 9v battery. I have a feeling its in the doors or the panel. Good luck

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Gentleman, thank you for all of your responses. My goal at this point is to disconnect whatever is causing the problem, if that is possible. My son is in a tight spot. If I can't get this figured out, the car will likely go to the junkyard for roughly $500.

I'll keep you updated.
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Most problems are usually something simple !

Quote:
Originally Posted by noego View Post
It's Deja Poo - as in, I've heard this **** before.
Steve

Calypso Red 1992 525i with 200K miles

1991 735i - Sold
1992 525i - Sold
1995 325is - Sold
2000 528i - Sold


Last edited by BMR_LVR; 04-20-2013 at 09:10 AM.
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  #10  
Old 04-20-2013, 10:21 AM
allenbee allenbee is offline
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Hi Steve,

I'm opening two windows on my pc, one where I'm reading your responses and the other where I'm listing my replies. Due to your long response, I though quoting it might get confusing. Please follow in tandem to your earlier replies in red.

A. The car can have a dead battery. Once started, a good alternator keeps it running under all conditions. Shut it down, however, and you won't be able to restart it. This is for both a dead and a flat battery. I had to deal with this literally 2 weeks ago.

B. That you don't have the batt symbol after the remanned alternator, and by implication, the symbol must have been there before that, strongly suggests the remanned alternator is ok.


>>>>

Connect your multimeter in parallell on both ends of each fuse, if you have the metal points showing on each fuse. Fortunately, the ends of the fuse on a MD are unbelievably easy to reach. They are exposed, not hidden like in the Bimmer. By in parallel, I assume you mean touching one probe to one end of the fuse and the other probe to the other end of the fuse right? Also, is this to be done with the fuse in or out? Is the car to be running or no

>>>>

C. The underlined portion is correct. The fuse must be in, not out. If out, you'll need to stick the probes into where the fuse would plug in, which defeats the time saving method of putting them on the two exposed metal ends of the fuse while it is still plugged in. Of course, if you have those old fuses without any exposed metal, then you'll need to remove it and stick the probes directly in.

The car must not be running as we need to detect static draws. When the car is running many electricals are in operation. The battery is being drained flat by a current draw while the car is shut down....if the car was running, the alternator would constantly recharge the batt and it would never get flat.

D. You must understand what in series and in parallel is all about. It is simple, and google will have instantly comprehensible diagrams and writeups which might take 15 minutes to understand the principles of. That's all you need. You must do this if not you'll be at sea over here. I suggest you invest the time to get this pat. It won't take too long. Youtube will have good videos for sure. Fortunately the words "in series" and "in parallel" are appropriate english descriptions to the thing so you can hold the idea without confusion. It is not always so.

E. If there is no significant voltage drop overnight, then yes there is no static current drain /short / etc. However, if there is a big voltage drop (1 volt or more), the most likely cause would be the static draw in this case. FYI it may also be due to a bad battery, which seems unlikely for a 1 month old of course.

F. Before you disconnect all electrical connections, please run the dmm in series with one disconnected batt terminal and its clamp, from the 10A setting all the way down. If you notice anything more than 50 milliamps, you've got a current draw.

Considering that the batt symbol went away after the remanned alternator was put in, your voltage readings while the engine is running are in range, that the battery is new, and that all this happened after a door accident (which cannot damage the battery and the alternator), it looks like a short in the door's circuit. The only thing that does not add up would be why the car dies even while running. That's not supposed to happen if the alternator is cool and even if the battery is not.

One simple way to check this fast is to wind the windows down so you can enter and exit easily, pull all the fuses for everything in the car except for the fuel pump and maybe the aux fan, then jump the car and recharge while driving, then shut down and see if it starts after 5 minutes.

The static current draw check will be conclusive in any case.

You are probably under 2 hours from isolating and either cutting off or working around the problem over here.

It might also be useful to remove the door card and see what's going on there. It might be something obvious.
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  #11  
Old 04-20-2013, 10:49 AM
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BMR_LVR BMR_LVR is offline
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Thanks. I eralized that I was not in the amperage setting so my testing was faulty. I have wathced a couple of good videos to get a better understanding of the testing process. I agree that is an inigma that the battery dies (i.e. the car dies) while running. Still scratching my head on that one.

Heading up there now to investigate further.
__________________
Most problems are usually something simple !

Quote:
Originally Posted by noego View Post
It's Deja Poo - as in, I've heard this **** before.
Steve

Calypso Red 1992 525i with 200K miles

1991 735i - Sold
1992 525i - Sold
1995 325is - Sold
2000 528i - Sold

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  #12  
Old 04-20-2013, 02:03 PM
allenbee allenbee is offline
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Quote:
Originally Posted by BMR_LVR View Post
Thanks. I eralized that I was not in the amperage setting so my testing was faulty. I have wathced a couple of good videos to get a better understanding of the testing process. I agree that is an inigma that the battery dies (i.e. the car dies) while running. Still scratching my head on that one.

Heading up there now to investigate further.
It might be a loose battery terminal or master connection to the alternator, since that repair was done recently.

It might also be a failing cps or fuel pump relay etc, unless they are fairly new. Stay open to the possibility that you have more than one issue at play. The current draw could be one and the other could be a natural wear and tear thing. When it rains it could well pour.

Last edited by allenbee; 04-20-2013 at 03:14 PM.
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  #13  
Old 04-20-2013, 02:09 PM
HipMusic Man HipMusic Man is offline
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Id say if the alternator is fine then its something else causing it to die. When the engine dies do the electrics as well? If so its the alternator or something drawing out too much power (ie a possible short, probably in the door due to the accident). If the electrics are fine when it dies check for a problematic sound in the engine. If it chokes out it might be the fuel pump or something

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Old 04-20-2013, 03:18 PM
allenbee allenbee is offline
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Just took a quick look through google. You might have issues relating to the dizzy cap etc. If, after checking all major wiring connections for looseness and damage, and ruling out a current draw, you have yet to solve this issue, it would be a good idea to take this to a chassis specific forum.

Secondly, if you feel you found some good videos on dmm use, would you mind posting the links here ? I could use a refresher and there are so many videos out there. Thanks.

Last edited by allenbee; 04-20-2013 at 03:20 PM.
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Old 04-20-2013, 04:02 PM
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BMR_LVR BMR_LVR is offline
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Mission accomplished Ö.Ö.Ö. I think.

I had my son charge the battery fully before I arrived. Static voltage on my arrival was 12.6 volts. I proceed to test for parasitic draw. It only registered 0.02. I had my son open a door (so the dome light would come on) and it went to 3.somthing. He shut the door, the light went out a moment later and the draw went back to 0.02. There were a couple of times I checked it and it had a high number like 5+. I'm not sure if it was an anomaly or I wasn't making good connections. So, since I could not see a parasitic draw, I told my son that I would just disconnect all electricals from the damaged doors.

I proceeded to remove the door panel for the driver's door and disconnect everything electrical. I replaced the panel. I went to the back door. I removed the panel. There was an electrical connection just behind the white plastic sheet that covers the door behind the door panel. We noticed that it appeared that this electrical connection had become very hot and seemed to have burned the plastic some. My son recalled recently that he had smelled something burning. I proceeded to disconnect everything electrical in that door as well and reassembled it.

After buttoning everything back up we checked the static battery charge and it was 13.1. Of course, the battery had been on a charge at 15 amps for an hour or two. We cranked the car and the alternator was putting out 14.1 volts at idle. I had him load it with turning everything electrical on that he could and it only dropped to 13.9. Yesterday, the most it put out was 13.5 volts at idle with no load. He drove the car a short distance and we checked it again with essentially no change.

I told my son to drive the car this weekend and every once in a while, check the voltage at idle and when the engine is off. He will be carrying my battery charger with him. I told him that, if the battery sustains at 12.6 volts or higher statically and 13.7 volts at idle, then to not put the charger (at 2 amps) to it.

Anyway, my conclusion (at least for now) is that my theory of the door damage causing the problem seems to have been correct. A couple of weeks driving the car will tell.

Thanks for all of the input and suggestions. I will update the thread in a couple of weeks.
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Most problems are usually something simple !

Quote:
Originally Posted by noego View Post
It's Deja Poo - as in, I've heard this **** before.
Steve

Calypso Red 1992 525i with 200K miles

1991 735i - Sold
1992 525i - Sold
1995 325is - Sold
2000 528i - Sold

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  #16  
Old 04-20-2013, 04:23 PM
bennyg1 bennyg1 is offline
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Glad you have apparently found the issue

I'm not sure I understand how that short could cause the car to die while driving, unless it was shorting through the chassis and draining the battery even while the alt was going fine?

In that case wouldn't a potentially dangerous current have been somewhere in the car?
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Old 04-20-2013, 04:44 PM
allenbee allenbee is offline
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Glad you killed that. No substitute for eyeballs. Looks like your static draw was more like 0.6volts. Interesting that this could not be detected during the static current draw check. Very interesting. Sucks actually ! But reminds me that baselining is very important for cars of our era.

The car still died twice while running. Did you figure that out ? Unless your son is a fan of anticipatory repair, I would still double check things.

Sometimes the car creates certain problems in order to highlight others. I had a wonky temp needle recently. Car seemed to run cold too much. It was persistent. Fuel economy tanked. Ects is new. No codes. 3 year old tstat. Diagnosis- thermostat right?

Turns out it was the temp sender sensor. But before that, I had changed the tstat to a lower degree one (80 degrees instead). In the process, the plastic thermostat housing broke apart thru no fault on my end. Turns out there had been a crack there all along, that could have ruptured full scale anytime. No obvious signs of coolant loss from there, but I was losing coolant slowly all the while. Thought it was something else.

Switched to a new aluminium housing, and the car runs better than ever. Good power and economy, the idle is a tad smoother, even compared to the time when all was ok. Coolant loss has stopped totally pretty much. So that was the culprit all along. There were no external signs at all.

After the change, noticed the temp gauge was still crappy so changed that a week later and all is good.

Note, though I'm using a lower degree tstat, the car heats up pretty much just as quickly as before on the stock tstat. I''ve read that it should take longer and that seems logical, but this is my observation. I'm using a Behr tstat, so that's oem.

Sorry for the long story but felt it helpful to illustrate that old cars, like old people, sometimes communicate differently.

Last edited by allenbee; 04-20-2013 at 06:10 PM.
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Old 04-20-2013, 05:45 PM
HipMusic Man HipMusic Man is offline
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Thats what I thought it was. Made sense that if the issue occured after the accident a connection was disturbed in a harmful way to the car. The first place to check is always the batter. Pretty much tells you whats wrong. Doesnt hold a charge its either a bad battery, short, or bad alternator. Rule those out and you have the "scene of the crime" the door panels or quarter panel.

Glad you got it figured out.

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  #19  
Old 04-20-2013, 06:29 PM
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BMR_LVR BMR_LVR is offline
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Originally Posted by bennyg1 View Post
Glad you have apparently found the issue

I'm not sure I understand how that short could cause the car to die while driving, unless it was shorting through the chassis and draining the battery even while the alt was going fine?

In that case wouldn't a potentially dangerous current have been somewhere in the car?
Me either. Of course, I really am a moron on electrical issues I'm just glad that the problem wasn't bad enough for the car to catch on fire I HOPE i've found the problem.

Quote:
Originally Posted by allenbee View Post
Glad you killed that. No substitute for eyeballs. Looks like your static draw was more like 0.6volts. Interesting that this could not be detected during the static current draw check. Very interesting. Sucks actually ! But reminds me that baselining is very important for cars of our era.

The car still died twice while running. Did you figure that out ? Unless your son is a fan of anticipatory repair, I would still double check things.

Sometimes the car creates certain problems in order to highlight others. I had a wonky temp needle recently. Car seemed to run cold too much. It was persistent. Fuel economy tanked. Ects is new. No codes. 3 year old tstat. Diagnosis- thermostat right?

Turns out it was the temp sender sensor. But before that, I had changed the tstat to a lower degree one (80 degrees instead). In the process, the plastic thermostat housing broke apart thru no fault on my end. Turns out there had been a crack there all along, that could have ruptured full scale anytime. No obvious signs of coolant loss from there, but I was losing coolant slowly all the while. Thought it was something else.

Switched to a new aluminium housing, and the car runs better than ever. Good power and economy, the idle is a tad smoother, even compared to the time when all was ok. Coolant loss has stopped totally pretty much. So that was the culprit all along. There were no external signs at all.

After the change, noticed the temp gauge was still crappy so changed that a week later and all is good.

Note, though I'm using a lower degree tstat, the car heats up pretty much just as quickly as before on the stock tstat. I''ve read that it should take longer and that seems logical, but this is my observation. I'm using a Behr tstat, so that's oem.

Sorry for the long story but felt it helpful to illustrate that old cars, like old people, sometimes communicate differently.
I did not figure out why the car quit twice while running. I have told my son to stay on top of this and check the battery voltage (static and at idle) frequently. We'll see if he does.

Quote:
Originally Posted by HipMusic Man View Post
Thats what I thought it was. Made sense that if the issue occured after the accident a connection was disturbed in a harmful way to the car. The first place to check is always the batter. Pretty much tells you whats wrong. Doesnt hold a charge its either a bad battery, short, or bad alternator. Rule those out and you have the "scene of the crime" the door panels or quarter panel.

Glad you got it figured out.

Sent from my SGH-T989 using Bimmer App
Yeah, that was my thought from the start. My son bought the new battery without consulting me and O'Reilly tested his alternator before I could and he bought a remanufactured unit. I just hope I solved it. If so, he at least has a new battery and "new" alternator :fingers crossed:
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Originally Posted by noego View Post
It's Deja Poo - as in, I've heard this **** before.
Steve

Calypso Red 1992 525i with 200K miles

1991 735i - Sold
1992 525i - Sold
1995 325is - Sold
2000 528i - Sold

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  #20  
Old 04-20-2013, 07:01 PM
allenbee allenbee is offline
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The car dying twice while running was not due to current surges or drains. I would strongly advise that the alternator repair wiring be rechecked at the very least. Grounds generally too. If not i bet you will have to do daddy duty again soon.

Found this recently, a good cheap very compact diy backup imo :

http://item.mobileweb.ebay.com/viewi...id=81476046907

Last edited by allenbee; 04-20-2013 at 07:03 PM.
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  #21  
Old 04-20-2013, 07:23 PM
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BMR_LVR BMR_LVR is offline
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Location: Asheboro, NC
 
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Quote:
Originally Posted by allenbee View Post
The car dying twice while running was not due to current surges or drains. I would strongly advise that the alternator repair wiring be rechecked at the very least. Grounds generally too. If not i bet you will have to do daddy duty again soon.

Found this recently, a good cheap very compact diy backup imo :

http://item.mobileweb.ebay.com/viewi...id=81476046907
I asssure you that I know how to hook up the alternator. I have not the tools nor knowledge to confirm how well the alternator was remanufactured. I have done to the car what I am going to do. I will wait to see how it goes. Just wait for my update in a week or two.
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Most problems are usually something simple !

Quote:
Originally Posted by noego View Post
It's Deja Poo - as in, I've heard this **** before.
Steve

Calypso Red 1992 525i with 200K miles

1991 735i - Sold
1992 525i - Sold
1995 325is - Sold
2000 528i - Sold

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  #22  
Old 04-20-2013, 07:46 PM
allenbee allenbee is offline
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Oh i didnt realise that you did the alternator job. EDIT I see you mentioned it in your op. My bad dad.

Then i would check whatever would be the usual suspects for that chassis. You already know what they are for the E34. Im not sure if it applies exactly.

Remanufactured alternators are opened up, visually inspected and properly tested before sale. Ive seen this being done and its a fairly fast job (the testing bit). Cheap components which require replacement are done and the unit is sold as remanufactured. More expensive components which require replacement would warrant the tag rebuilt if replaced with new components not good used spares, and are sold at a higher price. The best alternator to buy would be new if you intend to keep the car - the cost differential is not ridiculous over the alternatives.

Last edited by allenbee; 04-20-2013 at 07:58 PM.
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  #23  
Old 04-29-2013, 06:19 PM
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BMR_LVR BMR_LVR is offline
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Well, my son sold the car. He actually got about twice what I thought he would. I never did figure out what was causing the battery to die when he was driving it. After the last time it died, I loaned him my battery charger and told him to charge it each night and while he was at work. He did so and was able to drive it daily without it dying.

I appreciate everyone's help. No need to respond to the thread any further.

/ Thread
__________________
Most problems are usually something simple !

Quote:
Originally Posted by noego View Post
It's Deja Poo - as in, I've heard this **** before.
Steve

Calypso Red 1992 525i with 200K miles

1991 735i - Sold
1992 525i - Sold
1995 325is - Sold
2000 528i - Sold


Last edited by BMR_LVR; 04-29-2013 at 06:25 PM.
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