Lights on, limp mode, need help

Let me start by saying I love my car... I want to keep it. 2003 330i with manual... fun, fun! I've had it for 3 years now. I have not driven it much for the last four months since I cannot rely on it.

Backstory:
About a year after owning was the first time this happened, driving down the street after leaving my house... limp mode ensued. Pulled over, turned off car, swore a bit, turned back on and it was fine. This similar scenario continued intermittently for the next year - maybe 1 time ever 6 months. recently it has become more prevalent so I am aware of what goes on - car may be driving fine, then bam! - service engine light, brake light (orange, not red) and the circle with exclamation light right above mileage counter, car loses power and sputters, I turn off and back on and it goes home or wherever just fine. Now, every time I start, lights are on, car idles funny and won't let you drive. I can put it in gear and it truly does "limp".. now it's just sitting in my driveway.

My husband is handy. He fixed the disappearing oil problem, he's tried to fix the airbag light problem (think the seat sensor may be the next fix on that one). He has an Autel CAN OBDII scan tool which throws up NO codes.

I have a list of things to look into after reading this site. Which particular thing do you think we should try first? I'm a bit overwhelmed but I really love driving this car and want to have faith in it again. Any help would be greatly appreciated!

Anne

First thing would be to get the codes scanned....Autozone will do this for free. Write down their findings, then post the results here, that will give us something to work with.

Called autozone this morning and as someone stated in another post, apparently CA passed a law that won't allow them to scan to diagnose anymore. They can test the battery though so I will take it out there later for that test.

Of course went out to make a video of what's happening this morning and it started fine.

I called the dealer and they said they would scan my key for for free otherwise I have to pay the dealer for the diagnostic test.


Thanks
Anne

Originally Posted by grrltraveler

Called autozone this morning and as someone stated in another post, apparently CA passed a law that won't allow them to scan to diagnose anymore. They can test the battery though so I will take it out there later for that test.

Of course went out to make a video of what's happening this morning and it started fine.

Is my only option to pay the dealer for the diagnostic test?


Thanks
Anne

Ask Autozone if you can *rent* their scanner, and do the scan yourself. It`s not difficult to do.

A more in-depth diagnostic scanner may give some insight.

Some things don't throw codes. I had some wiring issues with my mass air flow sensor (wire extended for supercharger) that would cause limp mode and not throw codes. So a failing MAF sensor (or maybe just dirty) may not throw codes right away but still cause problems.

Definitely get your battery tested. A low/failing battery is known to cause weird issues and not throw codes. You've had the car three years of nine .... If unsure it has been replaced and it's a BMW battery, good chance it's the original. Can get an AZ duralast or Walmart Everstart for reasonable. Batteries usually average 6 or 7 years. I got 9 out of mine. No real funky issues, just got to where I could barely start the car.

I brought the car over to autozone and they tested the battery it was perfect.I had found a receipt in the paperwork to show it was 3 years old. They don't rent out the scanner or lend it out so tomorrow I'll call around to try and find an independent who will scan her for codes.

Thanks all

Anne

More often than not its the TPS that is inside the throttle body that fails. It is an integral part of the throttle body itself, so you have to replace the whole thing. I'd go eBay or salvage. If you go salvage, pm me and I can hook you up.

Hi all,

We did a search for the sensor online with no luck. The only one I've found is a Universal Fits all size... Not sure I would want that? Does anyone have a part number and/or a website to check? I'll keep looking but in case you did....

So far I've looked at partsgeek, partstrain...

Thanks!

Check some of the site sponsors. One I buy from frequently: oembimmerparts

http://www.oembimmerparts.com/produc...6786281e46.htm

EDIT: Sorry, it says for auto or smg transmission only. Hmmmm.....

So.... Pedals are different on the auto trans, so there are two different part numbers. to make sure you're getting the right part in the future, go to realoem.com and enter the last digits of your VIN as requested, then browse the parts diagrams for what you're looking for. then you can google the part number and go with a recognized vendor. ECS Tuning appears to have one:

35426786282

http://www.ecstuning.com/ES254838

Wonderful! You are such a huge help. Thanks for that.

So, I promise... last question... it appears the sensor is on the side of pedal once you pull it out? Is there no way to replace just that part? I am getting from your posts that the only way is to replace the whole pedal...

Thanks

Originally Posted by grrltraveler

So, I promise... last question... it appears the sensor is on the side of pedal once you pull it out? Is there no way to replace just that part? I am getting from your posts that the only way is to replace the whole pedal...

Thanks

That's what it looks like - everything I'm seeing is telling me it's all one part. Unfortunately, there are a number of parts that are like that.

Replaced the pedal with a new one today, same issues Is the TPS in the throttle body the only one in the engine bay or is there another one too? Assuming that's our next step, miss my baby

That's too bad. Looks like you're looking at a new throttle body then. That's under the hood and takes a little work to get to - removing intake tubing etc. You should clean your idle control valve while in there and if you haven't replaced your crankcase vent (CCV), now would be a good time.

In doing some of my own limited research on this, if your TB has a manufacture date of pre 1/5/02 (May 1) then it's pretty much guaranteed to fail prematurely. Otherwise it's just luck of the draw. There's also an engine wiring harness problem that can give these symptoms/codes and that's when it gets really serious. More expensive and a lot of work to completely replace the harness.

If hubby is pretty good with this stuff, he could probably swing it. Look for bavauto's youtube video on the ccv replacement. If your ccv has been replaced, just watch to the part where he takes out the throttle body. Otherwise it's a good tutorial all the way to the CCV.

Just thinking what else - your intake tubes could be a little brittle from age so they might not survive the procedure without being very careful with them. Again, a car at this age needs some refreshment parts so keep in mind. But get it going again! It's a shame to not drive it.

You could try to return or sell the new pedal after you get everything fixed and confirm the old one still works.

Originally Posted by grrltraveler

apparently CA passed a law that won't allow them to scan to diagnose anymore.

I researched this.

There is no such law.

There 'is' a reason though ... and it's in these threads:
- Which states make OBDII scanning illegal by the auto parts store? Why?
- In California, what establishment do you use to read OBDII codes for free?
- Cheapest CAN OBDII scanner on the net that reads DTCs, pending codes, & clears codes
- OBD II PC freeware & $15 J1962 cable for the BMW E39
etc.

Sorry for delay, just getting back to this after Christmas.

We took out the DISA and intake boots and have ordered new intake boots.

1) The DISA is dirty, oily crud. Can this just be cleaned, if so what's best to use?
2) Our plan is to clean TB using TB cleaner and then put her back together to see if that was it.

If not we'll buy a new TB. Is there anything else we should do/replace etc whilst we're in there?

Thanks

Be careful with the DISA. If the flap is relatively loose it either needs to be rebuilt with one of the kits that's been posted about recently or just get a new one. IF it's holding up well, I would just spray a little wd-40 on it or something similar and wipe down with paper towels. I've read some of the crud doesn't always come off as it has more or less bonded to the plastic. The flap should just rotate with some spring tension resistance and not much play otherwise.

Definitely clean the idle control valve - look for the diy. it's easy, much like cleaning the tb.

Honestly, if you're going to take out the throttle body, you're almost all the way to doing the CCV/oil separator and related hoses at the same time. will add an hour or two to the job but will save you a few hours on a CCV job since you've got all the intake tubes out and the TB and ICV. your car is pretty much due for it if it hasn't already been done. Anything more than light oil residue in the intake might indicate your CCV is starting to clog and send more oil-laden vapor into the intake.

I have 85k miles on mine and am planning to soon replace the CCV along with cleaning the ICV and TB. I'm also going to replace the oil filter housing gasket since it's somewhat in the area as well. I have a supercharger so it's more hassle to take that out and the intake tubing to get to all this stuff so I'll be working on the car for a full day to get all this done. It's a mid-life refresh in my opinion so I don't plan on having to do it again in the lifetime of the car, i.e. 150k miles or more.

Update,

So as we await delivery of new intake boots today hubbie took out the icv and cleaned it up and reinstalled it. He also started to clean the TB but when I press the throttle down from inside the TB plate doesn't open. When I turn the key to the second position(dashboard lights) the throttle plate opens about 1/4 inch but no more, even when I press on the throttle. He had read that as this is a drive by wire (2003 330i) he shouldnt push on the plate with his finger in order to open it. When it opened that tiny bit he sprayed TB cleaner in there. Should that plate open to the horizontal position when throttle is pressed inside the car or is this correct?

We swapped out the throttle pedal for the new one thinking maybe that was it but it made no difference We're thinking the a new TB is in our future.