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Old 01-10-2012, 12:40 PM
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Once warmed up, engine rpms surges 1500-2000

I have a 1989 Formula with 350tpi. I didn't have time to change the EGR valve so I paid a shop to do, Long story short I got the car back barely running. Distrib not tight, connector not connected, and the plenium bolts were loose or missing all together. I replaced the gasket, tightened everything up. Reset the iac. When you put your foot into it, the car still has crazy amount of power. Also I had just replaced the MAF as it was giving me that code. Now there are no codes. Also, running to rich, exhaust makes eyes water.

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Old 01-10-2012, 06:50 PM
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Not sure why this is in transmission forum... moving
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Old 01-10-2012, 09:30 PM
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Possible the EGR isn't functioning as it should and running rich due to the expected EGR air not entering back into the intake? I'm surprised with it running that rich there are no codes. Unless it's dual exhaust all the way back and the only side running rich is the one without the 02 sensor.
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Old 01-14-2012, 09:24 AM
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Have you checked for vacuum leaks?
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Old 01-14-2012, 10:37 AM
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Look at the live data stream for anomolies.Check any component that has a value beyond the normal range for an engine at idle. Check the TPS value, someone may have been cranking the throttle plate open to compensate for an EGR hanging open.


Perform a fuel pressure test to be sure it is correct, a pinched return will raise pressure to deadhead pressure of about 100 psi making it rich.
As turboS10 suggested look for vacuum leaks/ check map sensor hose( I think that one still has a MAP sensor as well as a MAF)

If you are absolutley sure the timing is correct and that there is no vacuum leaks , then I would try performing a minimum air rate adjustment as I suspect someone has been fiddling around with the throttle stop/tps adjustment. Keep us posted. LA Tech
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Old 01-18-2012, 01:17 AM
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It is NOT dual exhaust all the way back and the O2s ok, But you got me thinking. The new EGR that had been installed by that unknowledgeable mechanic could be faulty. The value on the TPS was way off (32.056) when it is suppose to be ( 0.54 - 0.59) Explained the rich. I had to go out of town for work and only just returned so I still have more to do. Thank all of you for your replys. It has helped keep me focus and temper under control. lol
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