E150 302 EFI 1988 cold start question !!!!!!!!!!!!!!!!!

Hi...... What is making the engine run at high idle when cold? (Choke as it whas on older cars.)

1988 E150 302 EFI. My cars idle seems to go down to fast at cold. Then it nearly stalls, and then goes up at idle again.The first 3-4 minutes when start at cold it idles high and fine as it shall do. The problem seems to be from that time and until it's warm. Runs fine at idle when normal operating tempratur. Have replaced for other reasons Upper intake manifold gasket and IAC. (Because I had high idle at all conditions. And that helped.) Have also had a troubble code from the EGR valve not closing sensor, but that went away when I cleaned the EGR from carbon builtup. Could it be the EGR valve that is worned out from all these years? Or is it any vacum valve that controls this? Janne....
Reply to
Tor Elling Rustad
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The water temp sensor for the ECU is possibly dead, so it can't tell that the engine hasn't finished warming up. There's a separate sensor for the temp gauge, so don't be fooled if the gauge works. IIRC they're both located on the lower intake manifold near the thermostat.

This is assuming that once the engine is good and warm it doesn't stall and the temp gauge reads normal. If it never recovers until the weather warms up you need to check the thermostat.

Sean

Reply to
Sean Conolly

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