Installed C5 longtubes, running terrible
Thread Starter
5th Gear
Joined: Feb 2024
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Installed C5 longtubes, running terrible
Hey so I just installed longtubes and a catted x pipe and when I start the car the check engine comes on but I still have all 4 02 sensors but I’m getting codes for them and codes for misfires. Is this common? Will a tune fix this? Thanks
Drifting
Joined: Jul 2004
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From: Pingree Grove IL
Yes, you need a custom dyno tune, check your spark plug wires, make sure they are connected and not touching the header. My automatic car dyno 340 wheel horsepower, I have a VR intake as well. A manual car should dyno 350-355 wheel horsepower. Take it to a dyno tuning shop.
Melting Slicks
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Sounds like you are in need of a good tune!
Drifting
Joined: Nov 2019
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From: SC
Make sure you have the o2 sensors plugged into the correct harness. Driver side sensor gets plugged into the harness on the driver side. People often get them switched up since the sensor points to the opposite side
Instructor
Joined: Nov 2016
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From: Pueblo West CO
Start by checking all your coils and wires for the misfire.
It's easy to plug the rear sensor into the front, or drivers side into passenger, and that'll cause problems And even though you installed a catted X-pipe (having breathable air will make your grandkids happy) you've changed the location of the cats relative to the engine. Which will affect numbers. Long tubs pretty much always require a tune.
It's easy to plug the rear sensor into the front, or drivers side into passenger, and that'll cause problems And even though you installed a catted X-pipe (having breathable air will make your grandkids happy) you've changed the location of the cats relative to the engine. Which will affect numbers. Long tubs pretty much always require a tune.
Le Mans Master
Joined: Sep 2017
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From: Pasadena, MD
2023 C5 of the Year Finalist - Modified
In the early 2000s I had a cammed, stalled, catless longtube camaro. Car was never tuned. Ran 11.8s at 118. Should you get a tune? Yes. Is that what is wrong? I doubt it. Like other mentioned, check you plugs, wires and connections.
Let us know what happens.
Let us know what happens.
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If you left your spark plugs in during the install, you may have cracked on, or pulled off the sparkplug wire.
You should not be having misfires from adding those modifications. The other issue for the CEL could be the moving or removal of the cats. Those codes would be normal for bolt ons with headers.
Phil
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You should not be having misfires from adding those modifications. The other issue for the CEL could be the moving or removal of the cats. Those codes would be normal for bolt ons with headers.
Phil
EMAIL: Tuning@TampaTuning.com
Website >>> https://shop.tampatuning.com/
CHECK OUT MY SHORTS : https://www.youtube.com/@tampatuning/shorts
Street Performance Tune Package starting from $390.00
Instagram: TampaTuning
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