2004 Grand Prix I changed the mass air filter
cleaned the throttle body put the sea foam in gas
tank when I mash on the accelerator it barks down
what could this be
Have you replaced the fuel filter,and or checked the fuel pressure to make sure fuel pump is running correctly?
Yes I took it to a shop and they couldn't find anything wrong with it
Is there and engine light on?
If you have no engine light,and fuel pressure has been checked,you may need to have the PCM checked and reflashed,reason why i say this is no engine light with car loosing power there is and issue with PCM.
Ok thank you I will try that next
Looking for a Used Grand Prix in your area?
CarGurus has 43 nationwide Grand Prix listings starting at $2,999.
Search Pontiac Grand Prix Questions
Are you a UK consumer? CarGurus now has a discussion forum in the UK.
Pontiac Grand Prix Experts