Help! My car has trouble starting/staying on!

[Murked Out]

Ok guys and gals,:help

I've been searching around the forum and I jus can't seem to find the answer.

Here's the problem: my car is a 98 540i has about 140k miles on it. Since I first got it a few months ago the car always took about 2 or 3 times to crank the car for it to start and stay on. Usually it starts, revs to idle, and then cuts off. But after it starts , it stays on and runs normally. As of about 2 weeks ago that is no longer the case.
Now it still takes about 3 times to start, but sometimes it just cuts off for no appearent reason. I could be driving for 2 mins or 20 mins and it will just randomly cut off. The "check engine" light is on, but that has been on since i got the car and the mechanics say it's because of the ICV.

So I went to Autozone and got a diag. Only thing that comes up is the alternator is charging slowly. Take it to a mechanic and after a very brief check, he can't find anything wrong besides the water pump is "going bad" and my ICV prolly needs to be replaced.

After searching the forums I see a couple things that seemed similar but not the exact same problems. So I followed the advice they were given. I cleaned the MAF and the ICV last night. It started up the first try and was running better than I've ever felt before. I drove it bout 30 mins and then pulled off the road and shut it off. Let it sit then cranked it up again. This time it took 2 times to start...but didn't cut off.


I know I haven't explored all the possible reasons yet. What am I missing?

Can anyone help me? (sorry for the long post)

[Al's540i]

have you changed your fuel filter?

[Murked Out]

have you changed your fuel filter?

I haven't. I asked the previous owner(my brother) and he says he can't remember....(which I'll take as a no)

[bschmidt25]

FWIW, I had a similar experience w/ my old VW VR6 and it was the ICV. Sitting at stop lights, it would shut off randomly. I could restart it right away and it was fine for a little while, but would eventually do it again. I could also tell when coasting if it was going to shut off when I stopped. Starting was never a problem, just keeping it running was. IIRC, it was simple to replace (2 hoses and a wiring harness) and not that expensive - maybe around $75 for the part.

[rufryder]

One way to test if it's an alternator (of course I could be wrong but have heard from others) that when you do start the car, remove the negative charge from the battery and if it shuts down in few min.... then chances are its an alternator.

Maybe the alternator not holding the charge?!

Others can contribute and correct me if I'm wrong. Sorry to hear about your car and best of luck.

[Al's540i]

At 140k miles I would change out the fuel filter. It's way past due and can cause problems such as stalling while idling, not starting up immediately, etc. Your's is cheap to since you have a pre-2000 model. It's like $18 plus two new hose clamps.

[Murked Out]

FWIW, I had a similar experience w/ my old VW VR6 and it was the ICV. Sitting at stop lights, it would shut off randomly. I could restart it right away and it was fine for a little while, but would eventually do it again. I could also tell when coasting if it was going to shut off when I stopped. Starting was never a problem, just keeping it running was. IIRC, it was simple to replace (2 hoses and a wiring harness) and not that expensive - maybe around $75 for the part.

Hate to sound slow, but IIRC? What exactly is that?


One way to test if it's an alternator (of course I could be wrong but have heard from others) that when you do start the car, remove the negative charge from the battery and if it shuts down in few min.... then chances are its an alternator.

Maybe the alternator not holding the charge?!

Others can contribute and correct me if I'm wrong. Sorry to hear about your car and best of luck.

I'll check this too but I've never had any electrical probs. Got a Pioneer in-dash, 2 amps and 2 12s...no cap yet:nono


At 140k miles I would change out the fuel filter. It's way past due and can cause problems such as stalling while idling, not starting up immediately, etc. Your's is cheap to since you have a pre-2000 model. It's like $18 plus two new hose clamps.

Ok. Cool. I'll search for the part and the DIY replacement.



Thanks everyone. Even if these things don't cure my prob it def will make my car run better/more efficiently

[bschmidt25]

Hate to sound slow, but IIRC? What exactly is that?

If I recall correctly

Sorry for the acronyms :)

[Murked Out]

If I recall correctly

Sorry for the acronyms :)

No, my fault for not reading it thoroughly...DAMN u public school system! Lol

[cal45fan]

One way to test if it's an alternator (of course I could be wrong but have heard from others) that when you do start the car, remove the negative charge from the battery and if it shuts down in few min.... then chances are its an alternator.

Maybe the alternator not holding the charge?!

Others can contribute and correct me if I'm wrong. Sorry to hear about your car and best of luck.

DO NOT DISCONNECT THE NEGATIVE CABLE WHILE THE ENGINE IS RUNNING!!!! THIS IS A BIG NO NO.

Also, alternators do not hold a charge:confused.

On my wife's ML430, this same symptom was happening. It will start when it wants to and very flaky when the engine is hot. It turned to be the Crank Position Sensor. Disconnect it and re-connect after 2 minutes. This is enough time to collapse the magnet inside the CPS. If after doing this, she starts right up without hesitation, the you found your problem. Good luck and keep us posted.

[Murked Out]

[/quote]On my wife's ML430, this same symptom was happening. It will start when it wants to and very flaky when the engine is hot. It turned to be the Crank Position Sensor. Disconnect it and re-connect after 2 minutes. This is enough time to collapse the magnet inside the CPS. If after doing this, she starts right up without hesitation, the you found your problem. Good luck and keep us posted.[/quote]

Crank Position Sensor? I'm guessin that has to be somewhere relatively easy to get to.
I'll search... Thanks, I'll check that too.
Can't hurt...it's free to check

Ok. Call me slow but I found the Crankshaft Position Sensor(CPS) and this is what I should just have to unplug for 2 mins and it should be fine?
Correct me if I'm wrong but this is under the car, to the right of the tranny?

Check the link, it's on page 54: http://www.e38.org/M62loc_view.pdf

[jamesdc4]

On my wife's ML430, this same symptom was happening. It will start when it wants to and very flaky when the engine is hot. It turned to be the Crank Position Sensor. Disconnect it and re-connect after 2 minutes. This is enough time to collapse the magnet inside the CPS. If after doing this, she starts right up without hesitation, the you found your problem. Good luck and keep us posted.
Crank Position Sensor? I'm guessin that has to be somewhere relatively easy to get to.
I'll search... Thanks, I'll check that too.
Can't hurt...it's free to check

Ok. Call me slow but I found the Crankshaft Position Sensor(CPS) and this is what I should just have to unplug for 2 mins and it should be fine?
Correct me if I'm wrong but this is under the car, to the right of the tranny?

Check the link, it's on page 54: http://www.e38.org/M62loc_view.pdf
I would recommend replacing it.
Camshaft Position Sensor (540 M62) (http://forums.bimmerforums.com/forum/showpost.php?p=9844722&postcount=66)

[Murked Out]

Ok, thanks again fellas.

As soon as i get some time to fix this I'll let you know which thing fixed it

[Murked Out]

Ok, so I went to a friend of mine who's a mechanic and had him run a diag. Turns out i was getting a "Camshaft Position Sensor A" error code.
So I bought a new CPS and replaced it yesterday. I started the car and it started immdiately. I was so happy.

Just to be sure, I started the car a couple times and after about 3 times of starting perfectly the car came on then stalled and shut off. I was so pissed!
I made sure everything was as tight as it could be and even "reset" the car by unplugging the neg terminal for about 10 mins.

Any ideas on what to do next? Please? I'm lost out here :dunno:

Anyone?