CODE PO300 Random Misfire Detected - @ Wits End!

[Schurkey]

Scan tool was from AutoZone!

Is it a piece of crap, or is it reliable/accurate/trustworthy? Doesn't matter who sold it.

 

[RawbDidIt]

Scan tool was from AutoZone!

Where it's from is not nearly as important as the make/model, and what it reads. If it will read P0301-P0308, great, but the cheap code readers usually only pop P0300 which is why we're all saying we need further information.

Sent from my SM-N976V using Tapatalk

 

[Sideburnz]

This weekend I should be able to get it up to a friend that owns a nice garage more importantly a top of the line code/scanner tool. I can collect more information then.

AutoZone's code reader will not give me individual cylinder info.

And to whoever asked it's got all new Delphi O2 sensors!

 

[OutlawDrifter]

I would check new parts for sure, you never know what you're going to get.

Clean all grounds on the engine and check the wires/plug going to the injection spider.

 

[Steve A]

The distributor drive gear in these engines are also prone to wearing down to a "knife" edge which will sometimes show up as a P0300 as well.

 

[Jdoggat22]

Ive had 2 true random misfires in my trucks history and plenty on other cars. Most common problem is the MAF.

1st. MAF was dirty. No MAF code just dirty from using a k&n filter, oil got on it. Clean the MAF, maybe replace it. Ive only heard bad things about after market MAFs also. Use a factory one.

With your scanner, look at live data and see what the MAF flow is. Then google what its supposed to be. Dirty MAF will read low flow numbers.

2nd. Occured at TC lockup. The TC clutch bearings when bad and cause a nasty random misfire at lock up. New torque converter and it was fixed.