Intermittent check engine light

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Feb 17, 2022 | 07:17 PM

#21

C5 Diag

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Joined: Sep 2013

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From: Cape Coral, Florida

Quote:

Originally Posted by Mineolajoe

No bucking at all. It runs smooth at all times.

If just a flashing MIL but no misfires felt a crank relearn should fix it…was this info passed on to your repair shops ??…they should have asked !!

Feb 17, 2022 | 07:23 PM

#22

charliebrown266

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Joined: Nov 2014

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From: toronto,canada

They should be able to see which cylinder is miss firing! using a scan tool you can go to miss fire counters and see which cylinders are miss firing! they will show history for each cylinder and live miss fires

Feb 17, 2022 | 07:32 PM

#23

Dcasole

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From: Atlanta GA

Quote:

Originally Posted by Mineolajoe

Do you use an oil catch can?

no sir , a catch can on a NA LT1 is a solution looking for a problem
Dave

Feb 17, 2022 | 07:36 PM

#24

Dcasole

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From: Atlanta GA

Quote:

Originally Posted by charliebrown266

Like I said above , i would not waste anymore time , ask your dealer to log the PIDS while the car is being driven , if the crank sensor is off , it will show on GDS2 , if an injector is bad ... it will show in the results, coil, wire ... or even the ecm as it could be something as simple as a bad ground

Feb 17, 2022 | 08:04 PM

#25

Mineolajoe

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From: Mineola Texas

Quote:

Originally Posted by C5 Diag

If just a flashing MIL but no misfires felt a crank relearn should fix it…was this info passed on to your repair shops ??…they should have asked !!

The light flashes, then stays on at intervals from 200 miles to 1,000 miles and goes off within 50 miles of coming on, usually. I have never felt any misfire.

Feb 17, 2022 | 08:13 PM

#26

Mineolajoe

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From: Mineola Texas

Quote:

Originally Posted by Dcasole

If the engine doesn't misfire during their time driving it and logging the PIDS, will it give any indication of the problem? I don't want them taking a 500 mile trip to wait for a misfire and doubt they would agree to it. It may go 1k miles before triggering the CEL.

They said multiple cylinders showed a misfire over the data span so no individual cylinder is the culprit. It is random.

Feb 17, 2022 | 09:33 PM

#27

Jeffstern

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Joined: Apr 2019

Posts: 254

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From: Charlotte, NC

Sounds like your willing to live with it, good luck. Anyway interesting post, I learned a few things.

Feb 17, 2022 | 10:05 PM

#28

Dcasole

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From: Atlanta GA

Quote:

Originally Posted by Mineolajoe

No but anybody who has any diagnostic skills will be able to spot inconsistencies in the PID data. A check engine light does not come on until the ECM registers many misfires . In your case I am confident that you are logging more than normal misfires during normal driving and don't know it as its probably just under the limit that sets a CEL . Find somebody who has diagnostic skills and you will find your problem as the answer is in the data ... is it electrical ? Is it fuel , is it air because you need all three for combustion

Dave