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Discussion Starter · #1 ·
I did it step by step..starting with resetting the IAC...setting idle in drive..etc.When I fired it back up the idle went right to 1100 rpm.When I checked the TPS initially it was at .62..I was able to twist it slightly to get a .57,but I'm guessing these arent adjustable,even after hooking everything back up,it was still reading .58.The IAC was also loose when I first went to disconnect it..it wasnt even hand tight.So it looks like I need to replace the TPS before I do anything else..sound right?
 

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Your TPS is probably fine. .62V and .58V are both perfectly fine.

1100 rpm sounds like the fast idle, it should drop down from that though.

Did you have to mess with your idle set screw much?
Did you remove the IAC for some reason?

If it hangs at 1100 rpm, then you have either a vacuum leak, or you did not set the idle properly.



Check your work against this method... (preferrably on a warm motor)

Jumper diagnostic ports A & B.
Key on.
Wait 30 seconds.
Disconnect IAC
Start engine.
Adjust idle set screw to maintain 450 rpm.
Kill engine.
Connect IAC, remove jumper.
Check TPS voltage... should be .54~.65 volts.
Start car. May take a little gas for a second or two until it starts operating the IAC properly.
 

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What part of the TPS is loose?

You can test it by measuring the resistance between a center pin and outer pin, while rotating the throttle. Resistance should change gradually with no surprises.
 

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Discussion Starter · #4 · (Edited)
yeah I did the process step by step from the manual..the IAC valve was loose..like I could take it out with my fingers..so I went ahead and pulled it out to clean it,but it was clean as a whistle..I still sprayed and wiped off the pintle.I just went out and checked and it's still only a little more than finger tight.I cant get a wrench on it and dont want to use channel locks on the body of it..could that be a vacuum leak?
When I started it after disconnecting it..the idle was at 500 rpm
 

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Most likely that's your problem.

Remove the IAC and firmly push down on the pintle to push it back in. It takes quite a bit of force to retract it. If it sticks too far out it won't install all the way, and will leak at the threads. I think the pintle base can't be much more than 1/4" above the threaded part.

The IAC needs to bottom out in the throttle body. I remove the TB and use a crescent wrench, otherwise it comes loose. There should be a gasket on there also.

Then redo your idle set procedure.
 

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What he said. On the TPS though, test it with an analog multimeter. This way as you rotate the throttlebody open you should see the needle move in a nice smooth motion. If it goes up, then bounces down and up again, the TPS is shot. The digital ones have a hard time picking this up.
 
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