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Engine revs after taking foot off gas pedal...

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Old May 17, 2009 | 12:54 PM
  #1  
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sdwndr
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Default Engine revs after taking foot off gas pedal...

This hasn't happened very often (about three times in the last two months or so), but sometimes after I accelerate away from a stop and then lift off the gas, the engine will momentarily rev a little higher, even though I've lifted my foot off the gas. The car drives perfectly fine other than that. Anyone know what might be causing this?
Old May 17, 2009 | 01:32 PM
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do you have an aftermarket tb?
Old May 17, 2009 | 02:19 PM
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Nope, no aftermarket TB. Just a C&L cold air intake.

Could this be from a dirty TB?
Old May 17, 2009 | 06:38 PM
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it could indeed be a dirty/sticking TB. if it continues after cleaning, i would look into replacing the TPS sensor.

i had some odd throttle behavior that was fixed by replacing this. takes 20 min and $70
Old May 18, 2009 | 02:31 AM
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I had this problem a few years back shortly after installing my JLT-II. It didn't happen all the time and wasn't bad enough to warrant fixing it at the time. I then installed a Bama tune and started getting a severe lope at idle - I cleaned my throttle body and MAF and never had either problem again.
Old May 18, 2009 | 11:56 AM
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I bought my 07 used with 14k miles and it does it more often than not. I thought is was me. Everything is stock as far as I know and it seems to do it more when it's colder out. The other thing I noticed is a slight hesitation in accelaration when first starting it after it has sat awhile. It still has the orginal filter which looks pretty clean.
Old May 18, 2009 | 12:14 PM
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Originally Posted by sdwndr
Nope, no aftermarket TB. Just a C&L cold air intake.

Could this be from a dirty TB?
Sounds just like an issue I was having. When I looked at the TB I found quite about of carbon build up around the butterfly valves. Cleaned infront and behind the valves and instantly noticed a better idle and elimination of rpm surging I was getting.

Scott
Old May 18, 2009 | 02:59 PM
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I get that often when i shift quick. I thought it was a lag in throttle/fuel injection resulting in a little more combustion when i press in the clutch. I guess i will have to check my TB. But the front of my tb looks clean.
Old May 18, 2009 | 11:27 PM
  #9  
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Originally Posted by kcmarti
I had this problem a few years back shortly after installing my JLT-II. It didn't happen all the time and wasn't bad enough to warrant fixing it at the time. I then installed a Bama tune and started getting a severe lope at idle - I cleaned my throttle body and MAF and never had either problem again.
+1

I had idleing problems, as well as what the op mentioned. Cleaned all the electronic connectors to the TB/intake and the MAF sensor, and everything was fine.
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