RWD - Idle Problems, 1500 RPM Warm and Normal When Cold

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Idle Problems, 1500 RPM Warm and Normal When Cold 900 1994

I need help getting the idle to settle down to a normal 800 RPM. It idles at 800 RPM when first started and slowly increases to 1500 RPM after a few minutes. The engine is a NA Bosch injection B230.
I have checked the ECT resistance at the ECU plug pins 5 and 13 and get 2500 ohms at 40-45 degrees F and 200 ohms at 195 degrees F (running temp.). That is about right according to the FAQs. The problem began shortly after I cleaned the IAC valve and the throttle body. The throttle body microswitch makes at idle and opens above idle like it should. I'm not sure what the 3rd wire on the microswitch plug does. I have double star washered the two brown wires on the intake manifold in case of bad grounds. I have wiggled the wiring around the microswitch and IAC valve and got no change in the idle.
Any ideas would be appreciated.
Mine:3-940s running, 1-740, 2-940 parts, dtrs:3-940s running


New 1 Idle Problems, 1500 RPM Warm and Normal When Cold [900][1994]
posted by  jd620  on Fri Oct 5 14:49 CST 2018 >

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