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Another Cold start idle thread

2K views 5 replies 2 participants last post by  BMWJNKY 
#1 ·
I have a 95 325ic that exhibits the following behavior during cold weather:
on cold start-up the idle is ok for about 2 seconds
idle begins to hunt and eventually oscillates out of control until engine dies
crank the engine again and same thing happens
throttle input is necessary to keep the engine running
driveability is ok, however when you stop the car, the engine begins to hunt again
When operating temp is reached, the engine purrs like a cat, no more problems!!

I've checked or replaced the following items:
installed new Idle Control Valve
checked Throttle position sensor - ok
checked engine temp sensor - ok
checked mass air flow sensor - ok
replaced cracked vacum lines and spray checked others
installed new spark plugs
pulled out about half of my remaining hair

So far no change. I need to mention this does not occur during the summer or on warm days!!

Any suggestions??:(
 
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#3 ·
Ops! missed that in the post, I replaced the boot from AFS to throttle body. I have never replaced the fuel filter. I assumed a dirty filter would cause problems all the time, not just cold.
 
#4 ·
scooterkail said:
Ops! missed that in the post, I replaced the boot from AFS to throttle body. I have never replaced the fuel filter. I assumed a dirty filter would cause problems all the time, not just cold.
Possibly but a fuel filter is cheep and easy to replace and should be replaced once a year as PM.

Have you checked the vac. hose to the fuel pressure regulator? You also might want to try a new DME temp. sensor, this is different from the sensor for the gauge in the dash. Have you checked for an intake or throttle body gasket leak? Another not so common problem could be your VANOS unit sticking.
 
#5 ·
I've got a new fuel filter on the way. Checked the vac line to the fuel reg. and throttle gasket today. They appear ok. I sprayed them down good, no increase in rpm. The DME temp sensor is the one I mentioned checking in the original post. The resistance was within spec ranges.

I don't think this model has vanos.

:mad: Trying new parts is difficult since all my parts are thru mail order. Shipping adds-up pretty quick. Nearest stealer is 100 miles away. None of the box stores have anything for this car!!
 
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