impala rough idle

2004 CHEVROLET IMPALA
127,000 MILES • 3.4L • V6 • FWD • AUTOMATIC
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THISMESSAGE
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idles roughly but as soon as I turn on my a/c it runs a lot better. I just replaced the oxygen sensor on the car and that helped out a little. When it begins to idle roughly I tap the gas pedal and it runs better for a few seconds and when I'm driving it usually doesn't misfire until I've been driving for a while.
May 1, 2015 at 6:22 PM
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KASEKENNY
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More than likely this is a vacuum leak, so we need to start with this guide to see if we have a vacuum leak or not:

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

If there are no vacuum leaks, then we need to check the other basics.

That means we need to check for codes and find out if we have codes:

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Lastly, we need to check the fuel pressure and find out if we have low pressure. I doubt this is the issue, but we need to rule it out.

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

Please run through all this info and let us know what you find.
Mar 10, 2022 at 7:06 PM