2003 Pontiac Grand Am RPM's dropping while driving

2003 PONTIAC GRAND AM
119,000 MILES • 4 CYL • FWD • AUTOMATIC
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KRISTAL4477
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  • 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 5:21 AM
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JACOBANDNICKOLAS
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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 9, 2010 at 5:19 PM
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KRISTAL4477
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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 1:41 AM
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JACOBANDNICKOLAS
  • Experienced Mechanic
  • 110,239 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 4:53 PM
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