M60 Stalling Problem

[Phil in Vancouver]

Hey Guys,
Just got back from a month off. Car started fine--1994 530i M60 5 spd, but stalled repeatedly at stop lights and at very low speed. Started back up each time no problem. No sign of tons of white or black smoke--just normal. Changed the fuel filter today, filled up the almost empty tank, and added some injector cleaner. No difference.

I read some of the archives and the likely culprits seem to be a vacuum leak caused by a faulty intake manifold gasket, crankcase ventilation valve, idle control valve, or fuel pressure regulator. I'm also getting the 1221 code.

Any thoughts what I should try next? O2 sensors? Intake manifold gasket?

Thanks for your help everyone!

Phil

[Mike]

Is it rough idling, or just an abrupt stall?

[Phil in Vancouver]

Is it rough idling, or just an abrupt stall?

[tim]

phil- there's a known problem with stretching in the throttle cable in the m60. Since all of the other things are much more involved- check it. 1221 code? bonneville site is down, but from memory that's lambda sensor I believe. Often caused by a big crack in the AFM boot- typically on the underside where it's not easily seen- causes a very lean mixture, so could lead to stalling. Could also be a bad air flow sensor.

Most of the other things you mention have bad idle as a symptom.

good luck.

[Phil in Vancouver]

phil- there's a known problem with stretching in the throttle cable in the m60. Since all of the other things are much more involved- check it. 1221 code? bonneville site is down, but from memory that's lambda sensor I believe. Often caused by a big crack in the AFM boot- typically on the underside where it's not easily seen- causes a very lean mixture, so could lead to stalling. Could also be a bad air flow sensor.

Most of the other things you mention have bad idle as a symptom.

good luck.

[Phil in Vancouver]

Yeah, there's definitely not a rough idle, so I'll follow your suggestions. Thanks a lot!
Phil

[tim]

Sometimes the ICV just goes too. That's why there's a date on it.

My money's on a crack in the AFM boot. Has it been cold recently? Dense air will make the problem worse- if air gets in after the AFM, the system can't adjust and thus it throws a lambda code. The lambda code is because the exhaust o2 doesn't match up with what the engine thinks it's putting in as far as mixture. Take the whole thing (the AFM boot) off and give it a good lookover. Clean the icv and throttle body while you're at it with some carb cleaner, or better, electrical contact cleaner.

If I'm right and its cracked, you can duct tape it up, until BMA gets you a new one.

Tim

[Phil M]

only has happened 3 times but it happens after ive been zooming along at a good rate of speed and come to an abrupt stop. never has happened when i had just been sitting at a stop light for a few minutes, it just happens right after the car is at a complete stop, but before it "rocks back". i guess the harder you hit the breaks, the faster the rpms fall. seems as if its going at a faster rpm and then rapidly falls.. it passes the normal 'sitting' idle at 750rpm and then stalls. i also have an O2 sensor i need to replace and have gotten a lambda code as well (even tho right now my code comes up 1444 (no codes to show)). same thing?

[Unregistered]

1. Leaking intake manifold gaskets. This was giving me the 1221 code. I replaced the oxygen sensors first and it did not fix the problem. I then found out from Brett Anderson it was probably the intake manifold gaskets. Replaced those and the problem with the 1221 went away. But the stalling did not stop.

2. The stalling was due to a bad "camshaft speed sensor" (PN 12 14 1 731 886). The stomp test did not reveal this code. I had to get the Peake Code Reader tool and this read the code. I replaced the sensor and that fixed the problem. No stalling or driveability issues since.

Hope this helps.

Jeff
'94 530iT (alusil)
'91 535i
'90 535i
'97 740i

[Phil in Vancouver]

I figure I'll inspect the AFM boot first, then it'll be the intake manifold gasket and next the cam speed sensor. Or maybe the cam speed sensor before the gasket. Hmmm. Anyway, I'll let you know about my progress. Thanks a bunch for all your help!
Phil.