PO300 - can scan tool pinpoint the problem?

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May 16, 2021 | 05:56 PM

Ruffturbo911

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PO300 - can scan tool pinpoint the problem?

Hello, my 01 TA with 62k just threw a PO300 which I picked up on my BlueDriver OBD reader and is running very rough with a strong gas smell. The car is all stock. Is there a diagnostic tool that can pinpoint individual coils or injectors?

May 16, 2021 | 07:18 PM

tblentrprz

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If you can see mode 6 data on scan tool you'll see individual cylinders. Swap plug, coil and wire into different cylinders and see where problem moves.

May 17, 2021 | 02:12 PM

Ruffturbo911

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This is about all I can see from my saved data. The mode 6 is a confusing list of values that doesn’t indicate where it relates to.

May 17, 2021 | 03:05 PM

Ruffturbo911

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Here is the fuel pressure

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May 17, 2021 | 04:47 PM

Kawabuggy

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0300 is random cylinder misfire... Any decent scanner can track the misfire counts, and you may be able to identify which cylinder is the culprit. Keep in mind that when 1, or more, cylinders are misfiring that raw gas and unburned oxygen is going down the exhaust, where the O2 sensor sees it and then thinks the engine is running lean... at that point the PCM commands excessive fuel trying to fix the "lean" condition... HP tuners can be used to track misfires by cylinder. Start there... Or any decent scanner such as Snap On, or Alltell (autell?)... keep in mind fuel pressure may be good at low RPMS, but may drop off from a weak pump at higher rpm's and cause a misfire. Check for burnt, or arcing plug wires on headers if you have them.

May 17, 2021 | 08:43 PM

Ruffturbo911

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Do you know of a how-to diagnose through HPTuners? At 300-350 I would go for that. I’m looking forward the simplest cheapest way to diagnose the problem without just changing parts.

May 17, 2021 | 11:42 PM

tblentrprz

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I don't remember the PID #s for misfires. Should find it on google. Don't look at min max #s, just look at the value field to see which cyls are not 0.