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Idle and trans problem

Iconic_Lunatic

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VX V6 AUTO.
Okay so long story short, I had a vacuum leak from my air intake pipe, fixed that but now my car is idling at 1200-1300rpm. Even when coming to a slow down/stop it still revs high. But when I cold start it idles fine in park until I accelerate then the revs stay high again and now my transmission is clunking hard when I put it into Drive, Reverse etc EVEN when its cold started and the idles are fine.
I'm guessing I have another vacuum leak which would explain the high revs but would it affect my tranny? Never had problems with my diff, tailshaft or tranny or any symptoms before hand.

Also before all this I did clean my plenum and throttle body out and put back together (with original gasket) and degreased my whole underbody of the tranny and gave it a gerny. Are there any sensor plugs or something I could have knocked off that would cause this or?
And my mate thought it would be a good idea to top up with more trans fluid which may have overflown it, could that cause clunky gears?
Honestly stumped on what it is.

Any help would be appreciated! Thanks gents!
 

ant797

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over full tranny possibly could be to much pressure in the transmission and eventualy it could burst seals ...sounds like your throttle plate is sticking open if it idles fine when cold then goes high after accelerating either that or something to with the iac
 

Iconic_Lunatic

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Could the throttle body being stuck open or IAC have anything to do with the tranny doing that? Or do you reckon I have a new completely different problem?
 

ant797

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I have read the coolant temp sensor for the ecu on automatics can cuase shifting problems and high idle if its not working right also throttle position sensor may do it
 

ant797

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Maybe check if you plugged the throttle position sensor back in after messing around with the throttle body
 

Utel67

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The transmission is clunking because the rpm's are to high, once you fix the idle problem it will return to normal, try disconnecting the battery for five minutes this will reset the PCM.
 

ant797

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The transmission is clunking because the rpm's are to high, once you fix the idle problem it will return to normal, try disconnecting the battery for five minutes this will reset the PCM.
i reckon he forgot to plug in the throttle position sensor
 

Iconic_Lunatic

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Nah all the sensors are plugged in properly.. I've just found out I do have a vacuum leak near the plenum/throttle body somewhere.. Its hissing haha
And utel67 it still clunks even when ive just cold started it and the rpms are normal.. Thats why im confused. I know it will clunk with high rpms but its doing it anyway
 
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ant797

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I dont kn
Nah all the sensors are plugged in properly.. I've just found out I do have a vacuum leak near the plenum/throttle body somewhere.. Its hissing haha
And utel67 it still clunks even when ive just cold started it and the rpms are normal.. Thats why im confused. I know it will clunk with high rpms but its doing it anyway
Guess you got to hope there related i dont see or experienced a vacuum leak causing a clunk in trans though
 

Utel67

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Move the gear selector from park to reverse slowly and watch the idle does the rpm flare up.
 
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