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High Idle: TPS or IAC?

Old May 12, 2013 | 10:15 PM
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I cleaned my throttlebody today, put everything back together, and now I have an idle at ~1000rpm after start up, and 1100-1300 after driving a little bit. In gear it drops to 700rpm. I tried adjusting the TPS, it's a renix btw, with no luck so I put it back to where the indentations were previously. Any ideas?

EDIT: I followed Cruiser's write up and could not get terminal D to read 83% of B's voltage. It stayed around .85V

Last edited by austinjoe13; May 12, 2013 at 10:18 PM.
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Old May 12, 2013 | 11:50 PM
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Did you disturb anything that might now be causing a vacuum leak?
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Old May 12, 2013 | 11:53 PM
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I don't think so, but I'm gonna check it out tomorrow. I did forget the MAP hose at first though. It sounded like it was cammed and smelled like gas lol.
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Old May 13, 2013 | 10:47 AM
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The TPS is shot. I hooked up two multimeters and the D circuit never rose past .844v while the B circuit went from 4.5-5v. So I'll be getting a new one soon :P
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Old May 13, 2013 | 07:04 PM
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Good job Joe. Triple check the hose from the throttle body to MAP while you're at it.
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Old May 13, 2013 | 08:41 PM
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Originally Posted by cruiser54
Good job Joe. Triple check the hose from the throttle body to MAP while you're at it.


High Idle: TPS or IAC?-image-1375237117.jpg
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Old May 13, 2013 | 08:48 PM
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^^^^^^


So:


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Old May 13, 2013 | 09:14 PM
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Determination. I like that.
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Old May 19, 2013 | 02:22 AM
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Ok, I got the new TPS on today. The tranny shifts MUCH better! But I've still got the high idle. Would the IAC cause this? I am but a young padawan, Master Cruiser

The idle bounces between 1000 and 1200rpm every 5 seconds or so
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Old May 19, 2013 | 07:12 AM
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Adjusted the TPS on which connector? The flat 3 wire or square 4 wire one?

The flat connector, engine side, is the most critical. The trans side is quite forgiving. Therefore use the engine side for sure and see what you get.
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Old May 19, 2013 | 10:06 AM
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I used the engine side. C is 17% of A, +/- 1%
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Old May 19, 2013 | 11:36 AM
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Originally Posted by austinjoe13
I used the engine side. C is 17% of A, +/- 1%
Good. Try 15% for fun.
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Old May 19, 2013 | 11:39 AM
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Originally Posted by cruiser54

Good. Try 15% for fun.
More power?
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Old May 19, 2013 | 12:02 PM
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No. Hopefully lower idle.

Ever done the sensor ground test?
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Old May 19, 2013 | 02:08 PM
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Yes, I did and the resistance was between 1 and 2 ohms. So I'll have to clean that up and replace the battery cables and engine ground.
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