2002 impala under throttle engines revs up and down erraticaly
garmy
01-30-2007, 11:59 PM
Hi just purchased a 2002 impala it has 200k miles on it and was running great uo until the other day when i was going up a hill and the car seemed to bog down then was ok for a sec then bogged down again got it home and when inpark if i put part throttle it seems ok but at full throttle the engines rpms go up to about 4 grand then down to 1500 then back up to 4000 again and again. I am getting no check engine light at all. Does anyone have an idea what might be causing this problem or anyone have a similiar problem to this any info would be greatly appreciated Thanks.
crazy Jim
01-31-2007, 05:14 AM
could be your throttle position sensor. hook up an analog volt meter to see if it has a bad spot somewhere throughout its range.
BNaylor
01-31-2007, 07:34 AM
It would be helpful to post what engine you have.
It sounds like you may have a clogged CAT convertor. 2001-2002 Impalas with the 3400 and 3800 engines were delivered with flaky CATs. GM extended the warranty to 10 years/120K miles, whichever come first. However, it looks like you are on your own as to replacement with your mileage.
Dear General Motors Customer:
As the owner of a 2001-02 Chevrolet Impala, Monte Carlo; Pontiac Grand Prix; or Buick Regal model vehicle, equipped with a 3.4L or 3.8L V6 engine, your satisfaction with our product is very important to us.
This letter is intended to make you aware that some 2001-02 Chevrolet Impala, Monte Carlo; Pontiac Grand Prix; and Buick Regal model vehicles, equipped with a 3.4L or 3.8L V6 engine, may have a condition where the catalytic converter is replaced due to complaints of lack of power or illumination of the Malfunction Indicator Lamp (MIL). This may be due to the front endcone insulation from the catalytic converter breaking away and blocking the front of the first catalyst brick and preventing the free flow of exhaust gas through the converter.
This is not a recall. Do not take your vehicle to your GM dealer as a result of this letter unless you believe that your vehicle has the condition as described above.
What We Have Done
General Motors is providing owners with additional protection for the Catalytic Converter. If this condition occurs on your 2001-02 Chevrolet Impala, Monte Carlo; Pontiac Grand Prix; or Buick Regal model vehicle, equipped with a 3.4L or 3.8L V6 engine, within 10 years of the date your vehicle was originally placed in service or 120,000 miles (190,000 km), whichever occurs first, the condition will be repaired for you at no charge .
What You Should Do
Repairs and adjustments qualifying under this special coverage must be performed by a General Motors dealer. You may want to call the service department at your dealer to find out how long they will need to have your vehicle so that you may schedule the appointment at a time that is convenient for you. This will also allow your dealer to order parts if they are not already in stock. Keep this letter with your other important glove box literature for future reference.
It sounds like you may have a clogged CAT convertor. 2001-2002 Impalas with the 3400 and 3800 engines were delivered with flaky CATs. GM extended the warranty to 10 years/120K miles, whichever come first. However, it looks like you are on your own as to replacement with your mileage.
Dear General Motors Customer:
As the owner of a 2001-02 Chevrolet Impala, Monte Carlo; Pontiac Grand Prix; or Buick Regal model vehicle, equipped with a 3.4L or 3.8L V6 engine, your satisfaction with our product is very important to us.
This letter is intended to make you aware that some 2001-02 Chevrolet Impala, Monte Carlo; Pontiac Grand Prix; and Buick Regal model vehicles, equipped with a 3.4L or 3.8L V6 engine, may have a condition where the catalytic converter is replaced due to complaints of lack of power or illumination of the Malfunction Indicator Lamp (MIL). This may be due to the front endcone insulation from the catalytic converter breaking away and blocking the front of the first catalyst brick and preventing the free flow of exhaust gas through the converter.
This is not a recall. Do not take your vehicle to your GM dealer as a result of this letter unless you believe that your vehicle has the condition as described above.
What We Have Done
General Motors is providing owners with additional protection for the Catalytic Converter. If this condition occurs on your 2001-02 Chevrolet Impala, Monte Carlo; Pontiac Grand Prix; or Buick Regal model vehicle, equipped with a 3.4L or 3.8L V6 engine, within 10 years of the date your vehicle was originally placed in service or 120,000 miles (190,000 km), whichever occurs first, the condition will be repaired for you at no charge .
What You Should Do
Repairs and adjustments qualifying under this special coverage must be performed by a General Motors dealer. You may want to call the service department at your dealer to find out how long they will need to have your vehicle so that you may schedule the appointment at a time that is convenient for you. This will also allow your dealer to order parts if they are not already in stock. Keep this letter with your other important glove box literature for future reference.
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