I have a 1992 940. It has driven for years with no issues. A few weeks ago the idle started running up to 3500 RPMs in park and neutral. The engine runs a normal idle in reverse, drive, low 1 and low 2. However, it runs rough in drive, backfires etc . . .

I have changed the throttle control valve, calibrated the throttle position sensor, replaced the crankshaft position sensor, and replaced the cold start injector. Problem not solved.

Has anyone else seen this before?

Engine Codes are as follows:
Bank 'A' Socket 2 = 321, 221, 121
Bank 'A' Socket 6 = 111
Bank 'B' Socket 3 = 122

Thanks in advance,

The Sweedish Wrench

 

Sounds liek a tear some where in a vacuum or intake hose.

 

Thanks for the input. I will replace the vacuum hoses and check for vacuum leaks with my hand pump.

Looking at some of the archive posts it would not hurt to give my throttle body a good cleaning as well.

Gary

 

i had this happen once....turned out to be a dirty throttle cable housing.