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About 3 weeks ago had trouble with me stock '89 automatic where I pulled into a stop for about 3 hours. When I went to fire it up the car started to run real rough, like firing on 6 instead of 4. My GM mechanic has a shop close by and he diagnosed as a bad MAF which he replaced(while I wasen't there with a new Bosch sensor. The problem is, it is always running on a fast idel. Like when pulling up to a complete stop, it's idleing at a grand and thens slowly goes down to 600rpms. I can start out without giving it gas and it wants to pull itself along. I questioned him regarding maybe an adjustment to the tps but he says. the new MAF wouldn't affect this. Still want to test the tps circuit but that not might help. Anyone experience a similar situation and what was the cure. Any other thoughts or ideas would be appreciated. Also, what is the tps voltage suppose to be, seems I read somewhere it was.5 volts and is the proper way to set it.
Thanks to all.
TPS idle voltage should be .54v +/- .075v
To check the voltage, turn ignition on and probe the top 2 wires on TPS. If adjustment is needed, loosen the torx screws and rock TPS, forward or backward to obtain correct voltage, then tighten screws.
You may want to set the minumum idle then adjust the TPS idle voltage.