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Discussion Starter · #1 ·
Been trying to figure out this high idol, I have good readings at the TPS-0.95 volts at the bottom and 4.95 volts when running. IAC reads 10.2 volts at proper idol speed and 8.4 volts when it idols up. The car starts fine, throttles up to about 1200-1300rpm for about 5sec then down to about 700rpm. About 10sec later it jumps to 1500rpm and stays there. When the IAC get unplugged the car all but dies, 200-300rpm. When the TPS gets unplugged it settles down to about 700rpm. No obvious vacuum leaks. I've used 3 iac's and 3 tps's and all read about the same. I can't let this continue, the car will run away with it's self too easy. The only other issues are the tcc locks at the same time it makes the 2-3 shift and seems to shift too soon threw all the gears. It also has a bad bank 2 sensor 2 o2 heater out. Any ideas would help, thanks for your time馃憡馃檹
 

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1995 Thunderbird LX Missing 4.6 MIssing Trans Red
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I assume this is for a Tbird. What year? What engine?
 

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Discussion Starter · #3 · (Edited)
97 4.6, I got to looking at things a little bit closer this morning and it looks like somebody messed with the hard set screw on the throttle plate. I can't honestly see it being a vacuum leak the way that it acts. It does act the way that it's supposed to for a very short while and then the idle just picks up out of nowhere. Anything over 0.65 volts no the center pin of the TPS at idol and it takes off to 1500+rpm. When I let off of it, it seems to stay in the throttle for a few seconds then settles down. It does have a bank 2 sensor 2 o2 sensor heater dtc. I also don't feel that it's shifting right. It'll go threw all the gears and lock the TC before I'm doing 30-35mph unless I've got it pinned to the floor. That might not be related but it could be, thanks for your help and please forgive my ignorance.
 

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OK. You should never dink with the screw, because it causes issues for the computer. It ends up being a variable vacuum leak.
So, first step is to clean the throttle body blade of all the gunk that will be on the backside. If the eGR nut comes loose easily, take the tb off and clean out all the egr passages. :) They will be full of crap, as will the whole elbow. Maf or carb cleaner is best; You'll use qtips and rags as well. Make it look like new. After you put it back together, take it for a drive until it's fully warmed up. Leaving it running, warm, unplug the IAC. If it's set too high, it will keep running. turn the screw down, until the engine just dies. Plug in the iac, and start it without touching the pedal.
If it starts and idles, you're about done. You need to drive it and make sure it doesn't die on stops. If it works, you're done.
If you have to give it a bit more for stops, go 1/16th turn increments, a little goes a long way.
 

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I met him in the 70's. He toured with the Sex pistols when they toured the south, trying to cause a stir. :) They played Atlanta, lol. This country bar near where we lived was one of the spots, and it was a trip. :) He was probably 15 or so, lol.
 
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