2002 LS 3.0 revving high at start up.

[PhotoGuyPat]

I have recently put a lot of work into my 2002 LS 3.0. New serpentine belt, new coils, new plugs, new cooling system. The car had been parked over a year and a half and after all these repairs I got it running for just a couple weeks. The past few days it’s been revving very high at start up, up to 3k on the tach. The transmission was acting very clunky so I scheduled to have the transmission serviced in a couple week, I will also have new cats and 02 sensors installed. Just to today I tried to drive a small distance to the convenience store and back. When I left the store the car would not accelerate with the pedal and was revving on its own. When I would press the gas it would cut the revs to nothing. I was able to barely get home by letting the car drive it’s self at low rev. Anyone know what’s going on?

 

[milehighmikey]

It sounds like you have a vacuum leak or something went wrong with your intake manifold re-installation after doing your plugs and coils. I had similar trouble and it turned out to be a severely cracked rubber fitting at the firewall end of the PCV line from the throttle body. Just for grins, take off the PCV hose to the throttle body and plug it while it is running. If the same thing happened to yours as did mine, you should see the idle go back to normal. If that works, then unfortunately, you may have the same cracked connector that i did, the 3/4 or 5/8" to 8mm adapter rubber connection to connect to the PCV metal line at the firewall end of the engine cracked in its midsection.

 

[PhotoGuyPat]

It sounds like you have a vacuum leak or something went wrong with your intake manifold re-installation after doing your plugs and coils. I had similar trouble and it turned out to be a severely cracked rubber fitting at the firewall end of the PCV line from the throttle body. Just for grins, take off the PCV hose to the throttle body and plug it while it is running. If the same thing happened to yours as did mine, you should see the idle go back to normal. If that works, then unfortunately, you may have the same cracked connector that i did, the 3/4 or 5/8" to 8mm adapter rubber connection to connect to the PCV metal line at the firewall end of the engine cracked in its midsection.

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Ok I will have to take a look at that. I appreciate the feedback!