98 trans am kickdown
#1
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98 trans am will kickdown but wont upshift until I let off the gas.
Drives fine if I drive it around "normal". Also makes a hissing noise under the car. HELP
Drives fine if I drive it around "normal". Also makes a hissing noise under the car. HELP
#2
Moderator
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The downshift and upshift are completely controlled by the PCM based on engine sensor values. If that hissing sound is a vacuum leak, it would completely through off the PCM and then your shifting.
Always correct all engines problems and scan for codes (correct engine ones if found), before trying to debug strange transmission problems.
Always correct all engines problems and scan for codes (correct engine ones if found), before trying to debug strange transmission problems.