Help please!!

[DINGDANG]

Back story- 2014 silverado 4.3l v6 60,000 miles. Devloped a misfire waiting in line to get oil changed took to part store and they told me that I had a misfire on cylinder 2. Changed plugs and wires on all 6 cylinders and still had misfire. Took back to parts store and because the check engine light was on and they told me fuel injectors so changed all if the injectors and intake gaskets. still have misfire, had compression check and it was good also done fuel pressure check and getting good fuel pressure. I'm not really sure what to do next the only option left on the ignition system is to change the coils, but don't wanna waste $ if I don't have to.

[Black02Silverado]

Try swapping coils and see if the misfire follows. Then you know what to change next.

[DINGDANG]

Replaced all 6 coil packs and still missing, not sure what to do next!

[DINGDANG]

Really wasn't sure what to do next so I just bought all 6 coil packs and changed them. drove it around and the misfire would happen intermittent and service engine light would come on and a few times the traction control light came on as well. Beginning to wonder if it's an issue with the active fuel management?

Edited May 8, 2022 by DINGDANG

[DINGDANG]

 Engine has a slight miss at idle, stumbling abit and the rpm will jump as well

[txab]

Post your fuel pressure readings. Also since you're doing everything else it seems, clean throttle body and MAF

Edited May 8, 2022 by txab

[DINGDANG]

On 5/8/2022 at 12:53 PM, txab said:

Post your fuel pressure readings. Also since you're doing everything else it seems, clean throttle body and MAF

Cleaned throttle body and maf sensor. now the coolant fans are running constant, not sure if they are related. No engine light but still a small hiccup when idling. Drove a few minutes drives good but the fans are running. Engine is running Normal temperatue also.

[DINGDANG]

2 hours ago, DINGDANG said:

Cleaned throttle body and maf sensor. now the coolant fans are running constant, not sure if they are related. No engine light but still a small hiccup when idling. Drove a few minutes drives good but the fans are running. Engine is running Normal temperatue also.

Will have to to fuel pressure again, don't have the fuel pressure gage anymore. Buddy done it for me.

[txab]

You don't remember the FP readings? Need to check them against the recommended spec.

 

So engine is running now with no miss? Or it just hasn't had time to show up? Did you disconnect battery while doing cleaning and use the proper cleaning agent?

 

[16LT4]

Wrong plugs, or go overboard with antiseize?

 

If the CEL was on, the DME has stored trouble codes.  What are they?

[DINGDANG]

3 hours ago, 16LT4 said:

Wrong plugs, or go overboard with antiseize?

 

If the CEL was on, the DME has stored trouble codes.  What are they?

Will check it out, went out to start it today and the battery is dead

[DINGDANG]

Ran crc intake and valve cleaner, still missing, cel came on and stayed on. Took truck auto parts store and reader said misfire on cylinder 5. Took out spark plug out and it was broken, changed it and the misfire went away and the truck is running good now. Looking into buying afm disabler to turn it off.