M20 stumbles

[Mr. BILL]

I replaced the battery and negative cable on my son's '90 525 w/219K.

It starts and runs now, but when you let off the gas and the RPM's drop to idle, the car almost stalls. It will catch itself and idle fine, but every time you feed it some gas and let off, it almost stalls.

Could it be the ICV?

Thanks in advance.

[bmwrp8]

clean your ICV...while cleaning do a DME reset by disconecting the batt.cables..then try again

[Blitzkrieg Bob]

on tight?

dirty ICV?

dirty ground contacts?

[SC David]

My car has done this each time I've replaced the chip. Seems to work itself out after an hour or two of driving, but since I've put the JC chip in, it still feels like it's going to stall sometimes when I shift from park/neutral into gear. Suppose it wouldn't hurt to check the ICV, but not sure if that would cause it problems while shifting into gear. I'm thinking maybe the chip and DME don't completely agree with each other :)

Sorry for the threadjack, just sounds like we are experiencing similar problems.

[BillionPa]

throw the batt on a trickle charge overnight.

[ruftek]

throw the batt on a trickle charge overnight.

I just installed a new battery and alternator on my 1990 525i M20 and had the same experience with a rough idle after disconnecting the battery! I think the DME may just need to adjust, because I drove the car very hard and it seemed to have fixed itself? I definitely know what you are talking about though.