Am I cant get my Idle below 1000, Ive try to ground out the blue and white test plug, I don't feel the humming coming from the air valve,all vacuum lines good ,I also hear the throttle switch click.

Got it!seems that the TPS was adjustment was off close it down and made some adjustments to Linkage ,and now its down to 740.Also my RPM gauge in the dash is off some reading 990,use my multimeter.

Have you cleaned the idle air control valve? Take it out and confirm operation with 12 volts. Dan

Ok,I did get it to drop down around 800,but as soon as I remove the ground it jump back to around 990 now.

Hi there,

I've found corrosion on the connector before. If you suspect the 1000 rpm idle is due to the valve with throttle plate and bypass screw closed tight, you can confirm the air path with a plastic bag.









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Art Benstein near Baltimore

Be nice to your kids. They will choose your nursing home one day.

Well I tried this and the engine wont run,check the plug also looks good.

Do as Dan suggests and test the motor by first applying battery across pins 1 and 2, then 2 and 3, using the middle pin as common to +. It should flop both ways.

If there's a possibility someone swapped the TPS plug for the idle motor plug, even for a short test, the ECU will need to be repaired or replaced. Confirm by back probing pins 10 and 23 on the ECU connector - while idling, each pin should average out less than battery voltage but greater than zero. Depending on your meter, the numbers may jump around. If either is steady +12 or 0, suspect the ECU is damaged.
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Art Benstein near Baltimore

Time flies like an arrow. Fruit flies like a banana.

That wasn't one of Volvo's brightest moves. The good news is the ECU can be found cheaply on ebay. Dan