Engine just shuts off while at a standstill in neutral

[GreenFrog]

This happened twice today. I was exiting a mall parking lot and was paying at the booth with my car in neutral and still (obviously). I didn't even notice that the engine cut off until I shifted into first and pressed the pedal and nothing happened. It definitely didn't stall in a jerky mess; it just died by itself.

The second time was at a traffic light. I was in neutral and not doing anything when the engine just died by itself (again, didn't notice until I realized pressing the pedal resulted in nothing).

I remember catching it happen a third time today and the lights at the middle top of the dash blinked a couple times before the engine died. I think it was the low oil light and one other light at the top, but I dont remember which ones they were. This car is still fairly new to me so I don't really know where all the lights are and whatnot. I also remember the Check Engine Soon light at the bottom left blink a couple times too and disappear.

What could this be? Other than this, I haven't run into any issues with my car so far (knock on wood).

[danewilson77]

1. Do you have any codes?

2. Has any maintenance recently been done?

3. I would start with the intake stream. Clean MAF sensor. Clean ICV. Inspect upper/lower intake boots. Inspect DISA. You can clean the throttle body as well by removing 4 additional bolts.

4. If 3 doesn't work...check fuel pressure at the rail.

HTC Thunderbolt+TT

[kayger12]

Was your AC on?

If so, Vanos could be a suspect as well.

[Hornung418]

My guess: Code P0340. Need to replace the intake camshaft position sensor.

Hurry back with the codes :)

RootedDROIDXstatus. Come at me, bro.

[danewilson77]

My guess: Code P0340. Need to replace the intake camshaft position sensor.

Hurry back with the codes :)

RootedDROIDXstatus. Come at me, bro.

Could be. I would hope if there was an SES light he would have said something.

HTC Thunderbolt+TT

[GreenFrog]

1. Do you have any codes?

2. Has any maintenance recently been done?

3. I would start with the intake stream. Clean MAF sensor. Clean ICV. Inspect upper/lower intake boots. Inspect DISA. You can clean the throttle body as well by removing 4 additional bolts.

4. If 3 doesn't work...check fuel pressure at the rail.

HTC Thunderbolt+TT

Not sure about codes.. Never ran the car for codes since purchase about 2.5 months ago. I probably should take it to an autozone and get it scanned.

No maintenance done. Only mods I have are AEs and the aFE CAI.


Was your AC on?

If so, Vanos could be a suspect as well.

AC was not on.

[danewilson77]

Do you have an SES light?

[mikeyb74]

Do you have an SES light?

Dane, He stated that it blinked a few times. I am betting that it's a defective intake cam sensor. Green Frog if it's that part make sure you buy a BMW part not an aftermarket.

[danewilson77]

OK. Codes should be stored. Get codes read and report back.

[GreenFrog]

Got my car scanned -- no codes. The guy at Autozone said my car was running slightly rich..

Anyway, the problem of the engine just cutting out is getting worse (i.e. it's happening more frequently). It only happens when I'm coming to a stop in traffic (i.e. slowly) and as before, there's no jerky commotion. It's as if the fuel just cuts out.

I think it may be an issue with the fuel pump? When I'm in neutral at a standstill, the tachometer moves up and down ever so slightly (maybe 50-60 rpms). Also, the car has trouble cranking from a cold start.

I also have another issue where there is a strange scrapping sound coming from the rear left wheel while in motion. The sound gets faster as speed goes up, so it definitely seems to be related to the wheel. It almost sounds as if there's a piece of metal hitting something as the wheel rotates. Sometimes the sound will disappear, but it's there 80% of the time.

Any thoughts what could be wrong with my car? I'm going to take it to a mechanic soon anyway (if I can find some damn time off my job) but I want to have an idea with what I'm dealing with.

[Hornung418]

I'm unaware if there are differences between M52tu and M54 engines, but your issue is exactly that of my 328i. Coming to a stop in gear, the second I took it out of gear, the car shut off at the light. Sometimes I didn't even realize it was shut off. The solution wasn't apparent right away, but it took several weeks of driving like this to trip the code. I had a really hard time starting and often times it would put it self in safe mode.

Solution: Intake Camshaft Position Sensor. I was at 106k and was the first repair I had to perform. Easy 2 hour job with cleaning the intake tract.

Could be a wheel bearing issue. Wait for Dane to respond.

[kayger12]

CPS is definitely a suspect.

Also agree on a bad bearing being the source of your scraping sound.

If you can lift the rear of the car safely, try to rock the tire alternating pressure at the 3 and 9 o' clock positions.

If you have movement, you have a bad bearing.

Droid X. Tapatalk. Use it.

[GreenFrog]

Another point of info: while the car has trouble cranking from a cold start, when it's all warmed up and I park somewhere and come back, it cranks perfectly without any hesitation. Dunno if that helps or means anything, but just throwing it out there.

As for the bearing, my roommate thinks that could be the issue as well. What would cause the bearing to go bad? The sound came about around 3 days ago? I don't have any lifts or jack stands so I can't perform that test you mentioned.

Stupid Boston potholes.. they're so bad!

BTW, thank you guys so much for the quick responses and insight!

[aurelius]

OP: how many miles on your car?

Here's some info from the Beisan Systems (vanos repair) guy, copied from an E46 "Common Problems" (http://dl.dropbox.com/u/17676561/BMW%20docs/E46%20Common%20Problems.txt) document:

"Camshaft position sensors can fail and cause problems. They will usually
produce a code, but they might initially malfunction without producing a
code. A failing exhaust CPS will cause light performance problems. A failing
intake CPS can cause significant performance problems.
Aftermarket CPS sensors don't work. OEM CPS sensors are only available
through BMW. OEM CPS sensors have a BMW logo and this can be used to check
if a CPS sensor is OEM."

[kayger12]

Bearings are just a wear part.

They wear out and need replacing.

The potholes can accelerate the wear.

Droid X. Tapatalk. Use it.

[GreenFrog]

61k miles...

[aurelius]

I would do the intake CPS and, while you're in that area, VANOS rehab, plus idler & tensioner pulleys, and serpentine belt.

You're looking at a little over 400 bucks if you buy the parts at the right places and DIY. That's with the easier (tho more expensive) VANOS repair option.

Ask questions here if you need sources for the parts and or DIY info.

Your motor will run better and you'll get noticeably better mpg.

[GreenFrog]

How much would it cost to get that all replaced by a mechanic? I do have an aftermarket warranty so I'm wondering if that would be covered by it.

[danewilson77]

Got my car scanned -- no codes. The guy at Autozone said my car was running slightly rich..

Anyway, the problem of the engine just cutting out is getting worse (i.e. it's happening more frequently). It only happens when I'm coming to a stop in traffic (i.e. slowly) and as before, there's no jerky commotion. It's as if the fuel just cuts out.

I think it may be an issue with the fuel pump? When I'm in neutral at a standstill, the tachometer moves up and down ever so slightly (maybe 50-60 rpms). Also, the car has trouble cranking from a cold start.

I also have another issue where there is a strange scrapping sound coming from the rear left wheel while in motion. The sound gets faster as speed goes up, so it definitely seems to be related to the wheel. It almost sounds as if there's a piece of metal hitting something as the wheel rotates. Sometimes the sound will disappear, but it's there 80% of the time.

Any thoughts what could be wrong with my car? I'm going to take it to a mechanic soon anyway (if I can find some damn time off my job) but I want to have an idea with what I'm dealing with.

Have done the inspection I recommended above? It would be nice to rule out the easy stuff.

HTC Thunderbolt+TT

[danewilson77]

How much would it cost to get that all replaced by a mechanic? I do have an aftermarket warranty so I'm wondering if that would be covered by it.

Mmm...I would just take it to BMW, have them figure put what's wrong, authorize no repairs, until you know how much. Doesn't sound like your gonna DIY any of it?

HTC Thunderbolt+TT

[GreenFrog]

Have done the inspection I recommended above? It would be nice to rule out the easy stuff.

HTC Thunderbolt+TT

No.. I'm mechanically retarded so I don't know how to inspect the things you mentioned except for maybe the MAF. Is that the plug that clips into my cold air intake? I installed the aFE CAI and I remember a sensor plugging into it. The other things you mentioned.. I have no clue what you're talking about.


Mmm...I would just take it to BMW, have them figure put what's wrong, authorize no repairs, until you know how much. Doesn't sound like your gonna DIY any of it?

HTC Thunderbolt+TT

No DIY.. Don't have the tools, time, or knowledge. Do you suggest I go to a BMW dealership instead of a bmw-specific mechanic? I'd probably pay for an hour of labor, I'm assuming.

[aurelius]

I would counsel against a dealership unless your trust fund has weathered recent market turmoil unscathed.

Look in the maintenance forum for a sticky on how to find a good local independent BMW shop.

Btw, we were all once brand new to this but the Internet has greatly enabled automotive DIY culture.

There are text and or video DIY procedures for anything E46 but if time, tools, a place to work, etc., are all in the way, go the indie shop route.

Note: 4 of the 5 items I recommend in my earlier post can leave you stranded and the 5th (vanos rebuild) will have to be done eventually and will pay you back in mpg as soon as it's done.

Warning: do not just tell some shop to rehab your VANOS unit. They'll bill you $500 (plus labor) for the rebuilt BMW version, which uses the same old problematic seals and you'll therefore be back on the VANOS down swing in no time.

[danewilson77]

No.. I'm mechanically retarded so I don't know how to inspect the things you mentioned except for maybe the MAF. Is that the plug that clips into my cold air intake? I installed the aFE CAI and I remember a sensor plugging into it. The other things you mentioned.. I have no clue what you're talking about.



No DIY.. Don't have the tools, time, or knowledge. Do you suggest I go to a BMW dealership instead of a bmw-specific mechanic? I'd probably pay for an hour of labor, I'm assuming.

Yes. I mean....us telling you what we think is wrong, may shed some light, but if you're not going to DIY, and take to an indy/dealer, they will figure it out and make the repairs. I mean...without looking at and performing some of the tests above, its just too hard to tell you what's up....for sure. Feel free to report back, with what they tell you is wrong. Especially if you smell bullshit.

HTC Thunderbolt+TT

[aurelius]

OP: didn't you have an extended warranty or was that someone else who bought a ZHP recently?

[MasterC17]

Make sure when you installed the AFE intake the harness that goes under the intake boots is in front of the MAF. Otherwise it can compress the boots and cause the car to run poorly. Unlikely if the car idles fine, but possible. While you are in there just make sure the boots aren't being constricted in any way. Easy/good place to start - car needs air.

[GreenFrog]

OP: didn't you have an extended warranty or was that someone else who bought a ZHP recently?

Correct. I bought my ZHP at the dealership at the end of June and got a warranty with it. I'm worried the CAI and angel eyes will void it though...


Make sure when you installed the AFE intake the harness that goes under the intake boots is in front of the MAF. Otherwise it can compress the boots and cause the car to run poorly. Unlikely if the car idles fine, but possible. While you are in there just make sure the boots aren't being constricted in any way. Easy/good place to start - car needs air.

Not sure what harness you're referring to -- again, sort of a car noob here. But I do recall being meticulous with my install.

[danewilson77]

Correct. I bought my ZHP at the dealership at the end of June and got a warranty with it. I'm worried the CAI and angel eyes will void it though...



Not sure what harness you're referring to -- again, sort of a car noob here. But I do recall being meticulous with my install.

Not sure either. The only thing I have that goes under boots is MAF sensor wires.

HTC Thunderbolt+TT

[Hornung418]

If the MAF is not perfectly horisontal, the readings can be off and effect performance. Always make sure you route the connections as similar to stock as possible.

RootedDROIDXstatus. Come at me, bro.

[GreenFrog]

If the MAF is not perfectly horisontal, the readings can be off and effect performance. Always make sure you route the connections as similar to stock as possible.

RootedDROIDXstatus. Come at me, bro.

Not trying to argue or anything, but how would the MAF not be perfectly horizontal? All I had to do was clip it in until it clicked..

[Hornung418]

Just try rotating the MAF 180° and judging the performance. I'm not sure why it happens. But it's effected me with a long tube CAI. Made sure to keep it level with stock factory settings for best results. aFe should have the option to clip in, so it shouldn't be an issue, but if not level it will rear it's ugly head.

RootedDROIDXstatus. Come at me, bro.

[aurelius]

Remove CAI, replace original, invoke extended warranty. Problem solved.

Note: since each service visit incurs a deductible, get as much warranty work as possible done on each visit.

Good: have an indie BMW shop do a full diagnostic scan and use that to request any necessary repairs you may not now know are needed.

Better: have that same indie shop do the repair work. Unless yours is an actual BMW CPO warranty, you can have the work done by any legit shop. This way, you start bldg a relationship with that shop. I don't know Boston but I do know it was the early US bastion of BMW fandom, therefore there must be a bunch of great indie shops. See my post #22 above re how to find one.

Possibly Best: be aware your extended warranty is very likely refundable on a pro rata basis. Depending on how much a refund would net you, you might end up with quite the maintenance and repair fund.

[GreenFrog]

Is there a possibility that an indie mechanic will turn a blind eye to my CAI and not void my warranty? I don't have my original intake parts on hand -- they're at my parents' place..

[Hornung418]

Your intake will have nothing to do with your warranty. I'd stop worrying about it. That only matters at the dealer; Which you should only go to if it's a CPO warranty.

[aurelius]

^^^ He's right. A 3rd party finance company will be paying the tab.

Be sure to have them do a full diagnostic scan. In order to do so, the shop in question must have autologic or GT1 diagnostic computers. Ask before you go. Not all indies have that stuff -- it's expensive.

[aurelius]

Any updates? Fix it?

[GreenFrog]

No... just never have time after work to get my car fixed.. just can never get out of the office before 5..

[aurelius]

You might go have the codes read again, assuming you've been driving it in recent weeks.

Then jack around with your intake and MAF, as outlined above.

At least you can do those things easily on the weekend, etc.

You might also check the calendar of your local BMWCCA chapter to see if they're holding a DIY event any time soon. Those are usually held at an indie BMW repair shop on Saturday mornings. The attendees and the shop techs would certainly help you out.

[GreenFrog]

One thing I've noticed is that if I crank the car halfway to get the fuel pump primed AND THEN cold start the car, it doesn't hesitate for 1-2 seconds. It's only when I cold start it and crank the car immediately that it hesitates. Is this a sign that the pump is going out? I'm gonna go out right now to check out the MAF.

[aurelius]

60k is pretty early for pump failure but if the filter is partially clogged, the pump is working harder than it would otherwise.

I would install a new filter. At the very least, you're at the right mileage to do that on a preventive basis. Remember to prime the pump 2-3 times after installing the new filter but before actually starting the motor. The filter is somewhat expensive due to the pressure regulator being a part of the unit. I bought mine HERE (http://www.pelicanparts.com/cgi-bin/smart/more_info.cgi?pn=13-32-7-512-019-M67).

Have the codes scanned again just to be sure you don't miss something else and throw your money down the wrong hole. If you're still having problems after that, replace the fuel pump. I saw the relevant Bosch 69497 pump on amazon recently for $95.

[llll1l1ll]

I hate to revive an old thread, but I'm currently suffering from a similar issue. I just replaced my upper and lower intake boots and when I started the car, there is now a louder sucking sound. When I give it a little gas, you can hear it sucking. I'm not sure if this is normal. I listened around and all the noise seems to be coming from the intake manifold.

However, for the real problem, my car has a newly developed issue: I'll be slowing down from any speed and when I hit the clutch and let the RPMs drop down from anything above 2,300, the car wants to stall. In fact, it cut off on me while taking a turn last night. So now, I have to hold the gas in a little while I'm braking. However, once I come to a stop, it idles fine. The RPMs fluctuate somewhat still.

I can't imagine there is a huge hole somewhere in the intake after the MAF. Otherwise, it would idle terribly, let alone even run. I have to get the SES light reset. I'll see if there are any new codes.

For the record, VANOS will be done in December.

[Hornung418]

Intake CPS. Also you can brake in gear. Sounds like you have a vac leak behind the manifold at the check valve.

[llll1l1ll]

Haha I know I can brake in gear! I'm not that big of a noob!

I figured it would be the CPS. I'll get one and have the shop doing my VANOS put it in. Also, you are referring to the DISA when you say check valve, right?

[Hornung418]

No. There is a vacuum check valve behind the number 6 runner. If it's coming from the manifold, then it's most likely a vacuum line between the engine and the firewall.

[echo46]

It sounds to me like you have a serious vacuum leak. Go back and make sure the the lower intake boot is properly attached. Also make sure that you tightened everything especially at the elbow joint where the upper and lower boot meet. If indeed it is a vacuum leak, once you find it it will cure your stalling issue.

[llll1l1ll]

I found it. I'm an idiot. The lower intake boot was hangin off the throttle body. It's all fixed.

[Hornung418]

I found it. I'm an idiot. The lower intake boot was hangin off the throttle body. It's all fixed.
Glad you found it.

[danewilson77]

I found it. I'm an idiot. The lower intake boot was hangin off the throttle body. It's all fixed.

Not an idiot. Now you know...that's all. You've got to get that tab in the perfect spot.

[echo46]

Yep, I've been there and done that. Feels good when you realize it's not a big deal.

[llll1l1ll]

Hahaha well I once again learned I just gotta remain calm. Those blasted nuts on the clamps were killing me.

[danewilson77]

Hahaha well I once again learned I just gotta remain calm. Those blasted nuts on the clamps were killing me.

What tools did you use?

[llll1l1ll]

A very tiny 1/4 in wrench, which sort of worked if I contorted my body in an awkward position. I had this screwdriver with the ability to flex in any position which came in handy here and there. For the most part, though, it was the fatigue of hovering over the car the whole time (I'm tall) while finagling a small wrench on a nut which I couldn't see. Plus, the added annoyance of consistently dropping the tools into the abyss below because my fingers lost all dexterity and subsequently trying to fish them out with a magnet on a stick.

Surprisingly, when I went to adjust it the next day, it wasn't nearly as hard for some reason. My legs still hurt from leaning over the car, though.

[echo46]

I hope you repositioned the clamps for easy on and off next time.

[llll1l1ll]

I sure as heckfire did!

[echo46]

That's what it is then.