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Discussion Starter #1
Occasionally when Im driving around, say in 5th at 40 or so, the RPM's will be around say 2k. Ill put the clutch in and shift out of gear to coast up to a stopsign. The RPM will stay at 2k until I tap the gas quickly, then it will return to normal idle. It does this at various points in the RPM range. Would that be a dying TPS, dirty/sticky maybe?
 

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Sounds to me like your throttle plate is sticking open. If the TPS was still reporting partial throttle when the throttle was closed, the ECU would dump too much fuel, and the engine would probably bog down instead of rev high. The actual throttle body would be closed, not allowing enough air for proper combustion of the gas.

You should be able to duplicate this at a stop, with the engine off... Open the hood, and try holding the gas pedal at the height you would normally have it at, for about 15-20 seconds or so, then release. If you don't immediately see the throttle linkage move back to the closed position, something is up.

Now, the TPS could be failing in such a way that it hold the throttle plate open, but I'm not sure how likely this would be. Look for:

broken/missing/weak springs on the TB and throttle plate assemblies
sticky accelerator cable
dirty TB (caked up gunk around the throttle plate holding it open.
possible interference from the cruise control system
 

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Or it could simply just be that the tach is sticking a little bit... Does it bounce around sometimes when you are accelerating? Mine does this same thing but I never bothered to pay any attention to it as I always assumed it to be an old sticking tach, and not a TPS problem. Just a thought,

AUstin
 

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Discussion Starter #4
Not the tach, the engine actually stays running at a higher RPM. My throttle cable has a kink in it where it goes into the casing at the engine side. Its been there since I got the car, and it only started doing this now. As for the throttle plate, Ill have to lookinto it tomorrow. As far as cruise, it doesnt work. Could it still interfere? Maybe, I dont know that much about cruise systems, maybe someone on here can clue me in.
 
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