Jump to content

P0300-multiple cylinder misfire

Grumpy Tooch

Recommended Posts

Grumpy Tooch Enthusiast

Grumpy Tooch

Posted
Posted

My check engine light keeps coming on and going off every couple of engine hrs. The code is p0300. I can reset it and it goes away for while or it just goes off. I really dont feel any issues with the way the truck runs. I might have smelled the CC maybe once (rotten egg smell), but not enogh times to suggest it is bad. Also, when the truck is cold and I get ot the end of my stree to pull onto the main rd ..I accelerate gradually and it feels like i loose power briefly then slowly comes up to accelerate normally.(only this time of the day)

txab Senior Enthusiast

txab

Posted
Posted

Check intake gaskets and check fuel pressure for starters

 

Mileage? No other codes ever?

  • 2 weeks later...
captainruss99 Enthusiast

captainruss99

Posted
Posted

As a truck tech, I see ghost code P0300 often, without missfire complaint. But you need a scan tool, not just a code reader. Quite often, a crank re-learn is needed. As miles add up, engine wear allows the crank sensor data to fluctuate. A re-learn will reset it to it's normal value. I always verify the missfire counts first, in case it's another issue. I also do this as a part of a tune up.

Grumpy Tooch Enthusiast

Grumpy Tooch

Posted
  • Author
Posted

It has been going on and off more frequently now that I have been doing more driving lately. Last time it came on the other day I got another code with it, P0455. I still dont feel any problems with the truck.

Chris Senior Enthusiast

Chris

Posted
Posted

I have it myself at idle. I think its my tune

 

Sent from my DROID RAZR MAXX using Xparent Red Tapatalk 2

Archived

This topic is now archived and is closed to further replies.

Go to topic listing

  • Latest Articles

  • Posts

    • BlueV8
      AFM Disabler Question

      By BlueV8 · Posted

      A complete delete is the most thorough mechanical solution, but it is also major engine work. On a quiet truck that is still under extended warranty, opening the engine purely as prevention is difficult to justify. A plug-in disabler stops commanded cylinder deactivation, but it does not remove or repair the collapsible lifters, so it should not be treated as failure insurance. I would keep the oil full, document the maintenance, and have any persistent tick, misfire, or loss of power diagnosed promptly. If the engine eventually has to come apart, that is the logical time to compare an OEM-style repair with a complete delete. The right choice depends on the truck’s symptoms, warranty status, expected ownership period, and whether the engine already needs to be opened. We explain that decision in more detail here—full disclosure, this is our own guide: https://www.bluev8.com/blogs/news/do-you-actually-need-an-afm-disabler   One exception: some 2021 L82/L84 trucks have RPO YK9, meaning cylinder deactivation was already disabled in the factory ECM; on those trucks a plug-in disabler is redundant, although the AFM/DFM hardware remains inside the engine.
    • mark249
      Help purchasing a touch screen digitizer

      By mark249 · Posted

      Brought my 2015 Colorado into the dealership to check my touch screen issues, had that ghost touch thing happening. They said I needed a new touch screen and they could either order me one for $500. The lady at the service deck was nice enough to tell me I could order a touch screen online for less, she did stipulate that the touch screen had to be factory OEM, you can't pair an aftermarket screen to my radio seeing it was 2015, it had to be a GM factory OEM only. I found a few on Amazon and Ebay by the numbers on the back of the old screen, DJ080PA-01A GM# 22740886, Some said "OEM" in the description and others just said "Replacement". Would a replacement be the same as a OEM as long as it had the same numbers on the back of the screen? In some of the descriptions they also show different brand names but same numbers, is that an issue?  
    • Donstar
      Navigating senior years.

      By Donstar · Posted

      I have both but typically use the 4 legged walker (wheels on front, ski's on back).   The four wheeler is starting to be used on "longer" outdoor walks.  The 4 legged walker is particularly helpful in practicing good walking posture.  Both of my knees are at different stages of recovery and I'm trying to not develop poor habits.  I can actually manage with a cane but it's very difficult not to favor one leg over the other.  My PT recommends I continue with my 4 legged walker for a while.  Yesterday was four weeks since my last knee replacement and I'm excited about my progress to date.  It has been a hell of a rough journey so far but it is exciting to witness  systematic and continuous improvement.  I went for years watching the decline of my "mobility".  It seems that everyday now I am alerting my wife to something I can do now that I couldn't a day or two ago!  I encourage anyone facing the prospect of knee replacement to share any concerns with others who have had the surgery.  It isn't an instant fix but rather is a considerable amount of short term pain for long term gain.  Recovery time and pain levels vary for individuals post surgery but the end results are typically very positive and I've never encountered anyone regretting having had the surgery. 
    • diyer2
      AFM Disabler Question

      By diyer2 · Posted

      The lifter issue can be dealt with by shorter oil changes and quality oil IMO.
    • diyer2
      Winter Returned

      By diyer2 · Posted

      Got heavy rain, hail and light rain yesterday. 

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...