E30 Build Thread

Another video, except of it running.



I installed the new coolant sensor, did nothing. Pulled the plugs, as I suspected I think they're wet with fuel and pretty beat. Bad FPR putting too much fuel into the engine? Or would the no AFM or intake or coolant temp sensor cause the computer to tell it to add more fuel?

looks like too much fuel, which could be from a faulty afm reading.

not sure why the coolant sensor beig unplugged makes it run, unless it runs in default mode.


trying to do additional diagnostics on this thing without an afm hooked up though is spinning your wheels. drop in a different unit, pref a known good one, and see what it does.

seriously though, you guys need to get a power graphing meter. they're invaluable. check with your local craigslist, pawn shops, flea markets, and even the tool dealers. they'll possibly extend you credit for a model that is outdated for the current technicians, but will still function properly.

just get an externally fused unit.

maybe i'll bring mine to bfe and we can do a little workshop on how to use it??




df

The afm is not hooked up, so would everything be set to default, and the fpr is simply putting in too much fuel?

Trying to get an afm! Hard to find unless an M20 M30 etc unit would work.

Sent from my ADR6400L using Bimmer App

cross the part number on real oem and see what else it fits.



df

Checking meow

Not finding anything that matches.

Anyone have a BMW junkyard around them? I have zero here.

Not close, but Vines Automotive in Bessemer, AL (250ish miles from here) has 40 acres of parts BMWs. Give Martin Fisher a call: 205-426-2697. Ask for him by name.

Hey Matt, does this help at all?

http://www.r3vlimited.com/board/showthread.php?t=253755

Originally Posted by jonesin

Hey Matt, does this help at all?

http://www.r3vlimited.com/board/showthread.php?t=253755

i don't understand it....resistance values and voltage values are the same thing....the afm is a potentiometer, and so it the element in the maf. the only difference would be a hz signal, which bmw did not use. (ford does)


i cannot say for certain what the values are on an afm, as i have not speced out the e28. i will, though, and based upon the schematics, will swap in a maf directly to see what the effect is. i have an afm from my m70 (essentially a 2.5 X 2) that i can play with, so we shall see what is what....


be kinda cool if you could swap out the afm for a maf, eh??




df

Originally Posted by jonesin

Hey Matt, does this help at all?

http://www.r3vlimited.com/board/showthread.php?t=253755

Hmm, that would be sweet!

Originally Posted by drivinfaster

i don't understand it....resistance values and voltage values are the same thing....the afm is a potentiometer, and so it the element in the maf. the only difference would be a hz signal, which bmw did not use. (ford does)


i cannot say for certain what the values are on an afm, as i have not speced out the e28. i will, though, and based upon the schematics, will swap in a maf directly to see what the effect is. i have an afm from my m70 (essentially a 2.5 X 2) that i can play with, so we shall see what is what....


be kinda cool if you could swap out the afm for a maf, eh??




df

Videos coming, I'll try and explain what's going on.



The first video (sorry it's kinda long) shows it running on first start up. As you can see, I give it throttle and it dies the first time. Start it up again and I can throttle it decently, the rpms are pretty high but then they start to come down and down until it dies. I keep the throttle steady during this.



After you see me do this a few times, it won't start anymore. I pulled and plug, here's the picture:



The I tested for spark, and sure enough it still has it. So it must be a fuel problem somewhere.





One more thing, here is the connector that comes off the O2 sensor, looks pretty bad. Is there a resistor or anything in there, or should I just cut and re attach?

Bored waiting for parts so I installed a new sunroof handle and a passenger inside door handle. I need to get some rechargable batteries so I can throw this cluster back together.



I also just scored an AFM, should be here next week!



DF, thoughts on videos?

i am not aware of any sort of resistor in the o2 sensor circuit. that corrosion, however, would add quite a bit of additional resistance in the circuit, so i would address that.


as for the vid, are you getting fuel pulse?? you can modify a regular 194 bulb to use as a noid light. i also have an led that i could play with to see if it would be brighter when lighting up, but have not gotten to that point yet. been busy.


will bring one with me to bfe, along with my additional 'tech toys' for diagnostics and give you guys a show and tell.

and tacos.

and y'all get to see cadence in person, too!!

but back to the no start, it *sounds* like a crank sensor signal is not getting to the dme. the distributor is 'mechanical', so it will create and collapse a magnetic field, inducing a spark. this will simply occur at 'base timing' since the dme is not controlling the advance. this is why i suggest checking for fuel pulsse with any vehicle that is equipped with a dizzy.




df

Alright, so how do I do this bulb test?


Why do you think a crank sensor would work the first few times I start it, then stop?


I fiddled with it more yesterday, when I give it throttle and the rpms start to die, I'm pretty sure I feel a miss fire. But when it isn't dying it seems to rev nicely.

Sent from my ADR6400L using Bimmer App

heat can be a factor, so that's a common tell of a crank sensor issue.

you could also have other issues, but i would check the injector pulse since that seems to be the most likely cause if the no start, which could point to a crank or cam sensor.


to do the bulb test, take a 194 bulb and pull the elements down to make it look like the bulb has 'legs'. take these legs and plug them into the injector harness instead of the injector.

crank. look for a slight/light blinking. it will not be very bright, and may simply 'blink' by glowing orange and then bot, then orange, then not. so it would be helpful to have a 2nd person for the cranking.



if that glows, then you have fuel pulse. this means the dme is trying to fire the cylinders. the next thing to check then is fuel delivery itself. not simply fuel pressure, but fuel volume as well. iirc these things may have 2 fuel pumps. one inline 1 in the tank.


hope this helps.



df

Thanks for the info! Going to go out soon and give it a try.


You are correct, from what I've read, there are two fuel pumps. I'll post again with results and/or a video.

Here are a few videos. When it's cranking, you can just see the bulb flickering, however when it's running, the bulb is bright. Normal? Should I check every injector?


On another note, it didn't seem to run much differently with the injector unplugged, thoughts?

do you have a cold start injector on the manifold?? if so, clamp the fuel line for it and see if that makes a difference. then check your carbon canister lines.

it should run like it has a miss because the fuel injector is unplugged.

unless you unplugged the cold start injector...



either way you have fuel pulse, so that's a good thing.





df

Never heard of that lol, I simply unplugged the injector in the middle of the fuel rail, only 4 of them that I remember


What am I checking for in the carbon canister lines?

fuel. not simply vapor, or smell of fuel, but actual fuel. sorta like along the lines of a bad fuel pressure regulator letting in additional unmetered fuel.

if you unplugged an injector on the rail then you should have had a definate misfire/stumble/poor idle. i did not see that in the vid, so check the cold start injector.



df

Originally Posted by drivinfaster

fuel. not simply vapor, or smell of fuel, but actual fuel. sorta like along the lines of a bad fuel pressure regulator letting in additional unmetered fuel.

if you unplugged an injector on the rail then you should have had a definate misfire/stumble/poor idle. i did not see that in the vid, so check the cold start injector.



df

Will do!


It does have a misfire/stumble/poor idle lol. But it didn't really seem different with that one unplugged. I'll try unplugging the other ones one at a time to see what happens.

Sometimes the idle is high, and sometimes it's low. I took starting fluid/brake cleaner everywhere and didn't notice a difference in idle.


HOWEVER, when I sprayed a little into the throttle body elbow, the engine actually idles down. Strange

Alright DF, may be coming to a conclusion.



Car will not start with the cold injector line pinched, once it runs, it barely does with it pinched, then eventually dies as usual. So I'm thinking that once it gets a little warmer the computer is telling it to shut off the cold injector, therefore making the car not start and die.

I pulled the injectors out and cranked the car, they BARELY spit anything out. Of course that wasn't a scientific test by any means, but I thought I would see more coming out, tons of fuel in the fuel rail though.


So I'm thinking the injectors are severely clogged? It has been sitting for about 5 years according to the PO. Gotta find the specs for them and get them tested.

Definitely sounds like it could be the problem to me. If the injectors are the same as an M42 (fat chance), I have at least one set for you.

if you have spare injectors laying around, drop them in and see what happens. even if they're the 'wrong ones', they should start and run better than what is in there.


i have an injector flow tester that i should have brought out to show you guys along with the power graphing meter, but i didn;t have a fuel guage to use as part of the demo.

the injector balance test is basicly a little box that powers up from the battery and plugs into the injecotr in place of the harness.

with the key on/engine off, read the static fuel pressure. hit the button on the tester, the injector will pulse and read the fuel pressure change.

then reset the fuel pressure by cycling the key and repeat for the next injector. record the findings and evaluate.


i got the tool @ pep boys for around 40ish, ithink. it's been so long ago. i have used it many more times though when in the shop. not so much now.


but yeah, it could be clogged injectors, which would explain the no change in idle when it was unplugged and fits the bogging down/off idle not running right condition.


let us know.




df

Hrm, so my stock M50 injectors might work enough to know if that's the issue?


Also, how and can I clean these?