2003 Pontiac Grand Am RPM's dropping while driving

2003 PONTIAC GRAND AM
119,000 MILES • 4 CYL • FWD • AUTOMATIC
Avatar
KRISTAL4477
  • MEMBER
  • 2 POSTS
when driving my RPM's slowing drop if its 3 it slowly drops to almost 2.5 then it kicks back in again almost like a surge or its missing. not sure what to check
Aug 9, 2010 at 12:21 PM
Advertisement
Avatar
JACOBANDNICKOLAS
  • CERTIFIED EXPERT
  • 110,175 POSTS
Has the check engine light come on? Have you checked fuel pump pressure? Has the fuel filter been replaced reciently?

Let me know.

Joe
Aug 10, 2010 at 12:19 AM
Avatar
KRISTAL4477
  • MEMBER
  • 2 POSTS
the engine light has not come on, the fuel filter has been changed, as for the fuel pump not sure how to check that i do know that is ingageing when starting you can hear it kick on, also there is no hesitation in starting so was hoping to rule that out, I also had the tranny flushed and new filter put in thinking is was slippage in the tran but that is now ruled out to,
I did get a new catalatic convertor put on because someone actually stole it off my car and they put a universal on my car it was cheaper since i had to pay for it, could that cause the fluxuation in the RPM's
thank you for your help
Kristal
Aug 10, 2010 at 8:41 AM
Advertisement
Avatar
JACOBANDNICKOLAS
  • CERTIFIED EXPERT
  • 110,175 POSTS
Honestly, I think it is fuel pump related. As far as the catalytic converter, a universal one is fine.

Here are directions and a video for checking fuel pump pressure and the regulator. It is easy to do. You will need a gauge, but most parts stores will lend or rent them to you.

https://www.2carpros.com/how_to/how_to_check_fuel_pressure.htm

Check that and let me know what you find.

Joe
Aug 10, 2010 at 11:53 PM