M42club.com - Home of the BMW E30/E36 318i/iS

DISCUSSION => Engine + Driveline => Topic started by: jthorsland on October 14, 2011, 06:52:32 PM

Title: Another M42 Idle Pezzle???
Post by: jthorsland on October 14, 2011, 06:52:32 PM

Transplanted an older M42 into my '93 318i. Everything plugged in fine except there was no boss on the block to attach the knock sensor - as a result, I get a 1225 code with the stomp test(knock sensor). Here is my problem - The car starts up immediately and idles steady for about 15 seconds, then starts idling very rough. If I try to drive the car it exacerbates the problem, no throttle response and idling at 400 rpm. as soon as the coolant temp passes 1/4 on the gauge, the car runs perfectly at all rpm's and idles steadily. I have cleaned the ICV, replaced the coolant temp sensor,checked for vacuum leaks as best I could. I am baffled, could the lack of signal from a knock sensor cause this? Any suggestions would be welcome.

Jay

Title: Another M42 Idle Pezzle???
Post by: DesktopDave on October 14, 2011, 09:09:21 PM

I'd check the AFM temp sensor.  Do you have the AFM resistor pack wired up?  I'd remove it if so.  I don't think it has anything to do with the absent knock sensor.

How old is the O2 sensor?