Fuel Injector Rehab

Phil Rose pjrose at frontiernet.net
Mon Apr 19 22:47:17 EDT 2004

At 2:32 PM -0700 4/19/04, Derek Pulvino wrote:
>Without getting into the rest of the discussion (but it is a 
>motronic system ;) ), I'll be curious to see what you find out Tom.
>I've got similar issues, doesn't start well when warm, and when I do 
>get the car started when warm, I need to keep my foot on the gas, if 
>ever so slightly, to keep the car from stalling for about the first 
>3-5 minutes of startup (warm only!).  No problem on deceleration (ie 
>bypass valve), and it's not consistent at hot or cold engine temps. 
>This leads me to discount the idle stabilizer.  The other thing I've 
>noticed is it only happens when outside ambient is about 70-f and up.

I seem to recall that "poor running during warm-up" was stated (in 
Bentley) as  a symptom of a defective coolant temp sensor. The 
coolant temp sensor...is the one located on the backside of the head. 
Anyway, I think what happens is: if the ECU sees no proper input from 
the sensor, it then will use a temperature from the IM air-temp 
sensor to guess at the optimum fuel mixture during the first few 
minutes of running. See Scott M's write-up:


Phil Rose
Rochester, NY
mailto:pjrose at frontiernet.net

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