Running weak?

1995 PONTIAC GRAND PRIX
95,000 MILES • 3.1L • 6 CYL • 2WD • AUTOMATIC
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PONTIACPEOPLEPERSON
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I have the car listed above SE model. it seems to be running weak, barely gets to 3,000 RPMs when flooring it. It still gets up to speed just I feel like with a V6 I should be thrown back in my seat, lol.

Any ideas? Brought it to the shop for a "tune up" and they cleaned the fuel system and installed TR55IX and 4641 tune up parts.

Seems to run a little better after that but still not enough power. It doesn't stall or anything. Has a little jerk in the idle maybe but very slight. Starts up fine and no check engine lights on.

Would love any ideas or suggestions.

Thanks!
Jan 18, 2021 at 6:51 AM
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CARADIODOC
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Has anyone checked for a plugged catalytic converter? A potential clue is the sound at the tail pipe will be a steady hiss instead of the normal pulsing sound. Your mechanic should have a back-pressure gauge to test for this. It involves drilling a small hole in the exhaust pipe ahead of the converter, then you stick the gauge's probe in there to measure pressure while the engine is running.
Jan 18, 2021 at 8:14 AM
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PONTIACPEOPLEPERSON
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Thank you! I'm not sure but I will look into it. Is this something I should get checked out immediately or am I good to drive it around for now?
Jan 18, 2021 at 8:42 AM
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PONTIACPEOPLEPERSON
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I can't hear any hissing, just "glug glug glug etc.."
Jan 18, 2021 at 9:07 AM
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CARADIODOC
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A plugged converter can lead to engine overheating. Another way to check for it is to unscrew the oxygen sensor. Leave it connected to reduce the chance of setting a diagnostic fault code. Also don't unplug it while the ignition switch is in the "run" position. Setting a fault code while working on the system can confuse mechanics in the near future when there's codes set that aren't really indicating a defect or problem.

You might also look at these articles:

https://www.2carpros.com/articles/engine-has-low-power-output

https://www.2carpros.com/articles/symptoms-of-low-engine-power

Low power can also be caused by a timing chain that has jumped one tooth. This starts to be a good suspect at the mileage you listed.

Whether it's okay to drive it depends on what is wrong and if it will get worse. Take a look at this article too:

https://www.2carpros.com/articles/bad-catalytic-converter-symptoms
Jan 18, 2021 at 9:44 AM
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PONTIACPEOPLEPERSON
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So i figured it out... My floor mat was stuck up under the gas pedal :~|

Much anticlimax.

Thank you anyways.
Jan 20, 2021 at 11:33 AM
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PONTIACPEOPLEPERSON
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oh, one other thing. the mechanic said I could get some kind of aftermarket sensor to help the car MVAP or MAP or i can't even remember. Any ideas what he was talking about?
Jan 20, 2021 at 11:34 AM
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CARADIODOC
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Not sure what he's referring to.

Happy to hear you solved the problem. That would take a while to figure out when you can't see it. Please come back to see us with your next problem.
Jan 20, 2021 at 1:08 PM
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