530i M60 hesitation/stalling issues

[Rusty Bavaria]

My 95 530i started acting up last week, where if I was at idle the engine would just quit, or if I were driving (highway speeds) it would suck the power down on the engine, causing the tach to drop about 500 rpm stay that way for a couple seconds and then return to normal. This happens very intermittently. One day the car would drive fine and then next it would act up a couple times on my commute to work. When it stalls there is no problem restarting, it fires right up. I noticed a couple weeks back that the idle was a bit more rough than usual, not enough that anyone besides me would notice, but I could feel it in the shifter when sitting at idle.

Friday when driving home friday the car started bucking while driving on the highway, where the car would lose power and then come back, lose power than come back etc, so whatever this is getting worse.

I pulled the codes this weekend and the faults read in this order, Camshaft sensor and then Mass Air Sensor. Before I go replacing parts in the car, would these symptoms sound like what would happen if either on these things were failing?

Thanks in advance
Jim

[Tiger]

I am thinking of ICV valve.

[Rusty Bavaria]

Would the ICV cause those codes to get thrown?

The last time I had an ICV fail was on my 86 325 and it would cause the car to idle at 2500 rpm! I'll check that out though.

Thanks

[Jr ///M5]

MAF Sensor is bad. If it hasn't already thrown a check engine light, then unplug the MAF and then start it up. It should idle and not buck around. It will throw a check engine light and you'll have to reset it after the MAF gets replaced. The computer will compensate (not very well) for the absence of the MAF and therefore the car will run, just not very good, but if it seems to have cleared up the jumping, bucking problem, then the solution is replacement of the MAF.

Hope this helps,
JR

[Rusty Bavaria]

Ok fired up the car this morning in 20 degree temps, idle was rough, but the car did not stall. Opened the hood and unplugged the MAF, which stalled the car, started right back up without the MAF connected backed out of the driveway and it bucked and stalled right in front of the house. That was enough to tell me I'd be taking public transportation today. MAF Sensor is not the culprit, I'm going to try to clean the ICV tonight and see if that helps, then it's on the the Camshaft sensor.

This car KNOWS when I'm busy at work and don't have time for it..grrrrr

[632 Regal]

when your all done with that stuff clear the computer codes. When she bucks kicks and stalls again you might want to think about changing the intake gaskets and front/rear plate gaskets. The rear PCV plate is usually not a bad idea to replace too.

[Tiger]

Yes, especially when you are doing all that work... change everything underneath that.

[Rusty Bavaria]

Tonight I cleaned the ICV, reset the codes, reset the inspection and took it for a drive, idle is better but started acting up again about 2 blocks from home (20 minute drive). Pulled in and took another fault code reading and this time it's only saying it's the camshaft sensor.

If I can get my hands on one tomorrow I know what I'm going to be replacing.
Good call on the ICV though, the idle does seem slightly smoother and the car seemed a bit more responsive, so I got something out of it.

The intake gaskets, valley pan, and other assorted head related stuff is all new, I had that done early 08, chasing down a rough running stalling problem that turned out to be the exhaust/emissions pump valve failing and allowing exhaust into the airbox. I have a late production 95 if the other M60 owners are wondering what I'm talking about.

Thanks for the input on this
Jim

[Tiger]

What about your crank position sensor? This is more common replacement rather than camshaft. If yours is original, then it is time to change it.

Alot of time, the fault code may not be exact answer... Like your MAF code... On typical car, it would spit out O2 sensor code but when you check live data on O2 sensor, you know they are working and then the answer is the MAF is bad...

[Rusty Bavaria]

True, I was hoping that clearing the codes would allow the real culprit to rise to the surface...

Now a faulty crank position sensor could set off an error for the cam position sensor? I was searching for info on both of these on this site and the rest of the BMW internet world didn't find too much.