2002 Chevrolet Impala Q&A
2002 Chevrolet Impala Question: Loss of power when downshifting at highway speeds. Plugged catalytic converter?
I have a loss of power (no increase in speed, etc) when stepping on the gas pedal and transmnission downshifts to a lower gear at say 60 mph. Transmission will downshift OK but engine seems out of power and cannot increase speed. This power is needed when coming onto a freeway onramp to match existing vehicle speeds. This has never been a problem in the past and I've already put in a new air filter and fuel filter. Could a plugged catalytic converter be causing this problem with no OBDII codes showing? - vettewine
DO U HAVE ENG CODES AND WHAT ARE THEY AND YES A PLUGGED CATT WILL CAUSE LOSS OF PWR - globalhelper
Agree with globalhelper. If able to , bring in and have the tech you talked to diagnose it. See if the story doesn't change when he stands to make money on it. Also , restricted exhaust will NOT always set code(s) as GH stated before. Good luck. - ziptie12