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PO300 Code

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Old Mar 12, 2021 | 06:38 PM
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Bryan250
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Default PO300 Code

I believe it may be the Torque Tube causing the issue.

Getting a PO300 code. The car is idling very rough.

I have checked the Spark Plugs, Coils, and Valve Springs.

The car runs fine and can go for a while without getting the code. But if i let it idle for mare than 5 mins or so it will start to run rough and throw the code.

I just recently put a 3400 stall into it and did it with out removing the TT I believe the tweaking on the TT may have blown that rubber bushing. But not sure if that could cause the engine to run rough.

Just for reference the car also has and AA kit, Catch Can, LT Headers with not cats....

Thoughts?
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Old Mar 12, 2021 | 09:14 PM
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For the average DIY’er without the right equipment (scope, scan tool) misfires will only involve swapping or changing parts and this can get expensive !!...you forgot injectors and you can usually tell if it’s ignition or injectors by looking at the fuel trims. A scan tool can also determine which cylinder or cylinders are misfiring.

Last edited by C5 Diag; Mar 12, 2021 at 09:16 PM.
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