Skip the auto shop - Our mechanics make house calls

Q: Reduced engine power 2004 Grand Prix

asked by on

My car keeps going into reduced power engine mode,I have replaced the accelerator pedal,throttle body,and maf sensor,the only code is showing is the oxygen sensor,but I don't think it's that,please help

My car has 180000 miles.
My car has an automatic transmission.

Hello - you don’t specific what code is causing the Check Engine light to illuminate (oxygen sensor problem), but a failure of the pre-catalytic converter O2 sensor could cause a Reduced Power experience. Failure of the O2 sensor can cause the engine to run too rich, passing unburned gas fumes to the catalytic converter, a real overheat/fire damage possibility. I recommend a Reduced Power inspection performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, and give you an accurate assessment of damage and cost estimate for repairs.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!
  1. Home
  2. Questions
  3. Reduced engine power 2004 Grand Prix

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Car not starting.

There are a lot of reasons a car won't start from a dead battery to internal engine problems. An engine needs three things to run: spark, fuel and compression. A trained technician, such as one from YourMechanic, has the necessary...

Q: Hydraulic chain tensioner not working.

Hi there. If the tensioner was removed, then when the engine cranked over the camshaft would not move causing the piston to come in contact with the valves. Then there would be a serious problem with the engine. Most likely...

Q: When I accelerate, my car hesitates, the rpms bounce, and sometimes i have a missfire flashing CEL

Hello and thank you for your question. With having your engine with bank 1 being lean (lack of fuel), the symptoms are showing that there is a problem with fuel delivery or excessive heat. If the EGR valve was to...

Related articles

Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.