1999 Chevy Corvette high idle speed

1999 CHEVROLET CORVETTE
35,000 MILES • V8 • 2WD • AUTOMATIC
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RONCASTLE
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Here is my problem. If I go from a standing position with the car in drive and the a/c on I release my foot from the brake with no foot on the accelerator and the car will accelerate on it's own up to about 28 miles per hour and the tach will read 1000 rpm's if I do nothing except put the shiffter into neutral the tach will shoot to about 1800 rpm's and still no foot on the accelerator if you do nothing and give the car about 10 seconds the engine will work it's way back to the 600 rpm idle speed from where you started. With this condition stopping becomes very jerky as the transmission down shifts under power with the brake on.
Your suggestions please.
Apr 16, 2008 at 7:03 PM
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SERVICE WRITER
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You need to see what codes are stored in the pcm. A parts store will have a code reader that is going to be needed to pull them. Post the codes, and we can go from there.
Apr 17, 2008 at 8:39 AM
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RONCASTLE
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I took the car into the dealer and they did a scan with a tech II, code P1416 was stored, they performed secondary air system circuit test, BNK2 SAI check valve sticking intermittently. and said that I needed 2 valves, 1 gasket KI and 32 CPR with a cost of about $700.00 dollars. I can not see the connection between the air injection valve and my problem with the accelerator gaining rpm's without pressing on the accelerator pedal?
You thoughts please.
May 1, 2008 at 10:01 AM
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SERVICE WRITER
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That code has to do with the left check valve, not the right...not sure of why the other side was replaced....Unless code p1415 was also present.

The PCM activates the air pump during closed loop operation to lower tailpipe emissions. The PCM nomitors the AIR system performance by watching the O2 voltages. There should be a high short term fuel trim condition (richer) when it is working properly. IF there is a high voltage refernce from the O2 it will cause a low fuel trim (leaner) condition. The low a short term fuel trim is causing a poor response at the accelerator because the AIR system is not causing the proper flow.
May 2, 2008 at 5:54 AM