Jump to content

Recommended Posts

Posted
On 6/11/2021 at 6:58 PM, Mobud said:

Did switching gas help with the misfire? My 21 Sierra has done it twice now dealer found p300.

I have a 21 AT4 5.3 V8, and I've had the check engine come on showing the same code, however, it went away.  I recently took a long trip, filled up at a local Walmart after I got back in town.  Fast forward a few days and my truck has developed a bit of a shake when driving, along with a bit of a slip when coming to a stop, along with check engine light flickering some.  Not sure if you have had the same symptom, but I am curious if I put a bad batch of gas in my truck.  Was curious if you have experienced the same.  

Posted (edited)

So I thought too maybe it was bad gas. Took to dealer once had generic 300 code then light flashed again stopped by dealership said it was same code so a tech went and go scan took I had misfires on 1&6 said they’ve had a lot of issue with the lifters collapsing due to a bad batch of parts. So next week they’re replacing all lifters.the tech also said usually by 5000 miles they will fail I’ve got 2700 on mine.

Edited by Mobud
Posted

this happened to me a few weeks ago and then shutoff later the next day. mine was unsettling as it came on while driving through some fields (hey it's a truck right?) nothing reckless, just pulling a turkey blind. Never noticed any performance issues but for having less than 10k on the odometer and just 2 years old... 

  • 2 months later...
Posted

So I’ve had both banks of lifters replaced in mine at about 2500 miles. Went another 2500 check engine light came back on supposedly had to relearn the cam shaft position sensor. Lasted two weeks came back on apparently they are waiting for GM to rewrite code but they can’t figure out how to fix the issue and that was a month ago with still no update. Good luck

Posted

I have a week old 1500 AT4, just threw the P0300 code with 967 miles on the truck, this is my very first GM product, holy crap, why can't American companies build a reliable product?!!  I don't want to drive a Japanese truck, but damn it, American cars are so freaking awful :(   I don't have time in my life to take cars to dealers, if this keeps happening, it's back to Toyota (where I NEVER had a single freaking issue with two of them in over 250,000 miles combined!)

  • 3 months later...
Posted

I'm following this thread.  My 2020 Sierra started with the check engine light flashing for 10 seconds.  Dealer puller the p0300 code.  The next day the truck shook with the check engine light and service ECS system.  Restarted the truck it went way.  Too bad I'm at 37K with just over one year of ownership.  

  • 3 years later...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Latest Articles

  • Posts

    • not all plugs will be used.  gm uses more generic harnesses that support most/all options, and if your truck doesn't have a specfiic option, the plug won't be used (commonly will have a dummy insert in the plug , or it'll be taped up, but some may just be left as is).  But it's sldo possible some p.o. has installed the wrong/cheaper parts that aren't correct for your vehicle...
    • First off, I'm not trying to just get easy advice/fixes for the issues I've noticed so far.  I'll be combing through the site via searches and such, and if past experiences are any indication, should find what I need.  For the sake of conversation, though, I figured I'd post the handful of things I've noticed in the 12 hours since buying my 2010 SLE CCSB.     Indicator lights: Airbag and TPMS.  The tire pressures aren't reading for any of the wheels, so I'm pretty certain the sensors were either removed, are damaged, or are otherwise inoperable.  I used to mount and balance tires 25 years ago but am pretty much ignorant when it comes to TPMS.  My 2006 didn't have the sensors and this might be the fourth vehicle I've owned that does.     Radio: Rear speakers aren't working.  I removed the driver's side rear door panel and checked the speaker and wiring.  I also removed the sill and b-pillar covers to check the wiring.  A few minutes of Google Fu showed that this is potentially a head unit issue.    Switches: Power mirrors don't turn left/right.  I ordered replacement driver's door switches that should arrive tomorrow.  The windows and locks work but it was only about $20 for all of them.  The driver's side rear window switch lets the window down but won't put it back up.  I think the passenger rear doesn't work at all.  In the coming days/weeks, I'll break out my multimeter to check all of that.   Unknown wiring harness: There's a box attached to the front driver's side of the engine compartment, right where the second battery shelf is located.  There are three plugs, one of which looks like it fits a standard headlight-style bulb (9007 or similar).  It doesn't look like it's plugged into anything.  I'll do some digging and if I don't see anything elsewhere on the site, post some pictures here.   Unknown plugs on brake booster: There are at least two female plugs on the brake booster that aren't being used.  I think it might be a replacement/aftermarket, so maybe those are used for a different application, as there don't seem to be any unplugged harnesses and no indicator lights are on.   Little squeaks when turning: Sounds almost like a bushing around the bed of the truck.  I'll have to pay close attention as I get more familiar with the truck.   Clunk on acceleration: possibly the infamous drivetrain clunk.  My 2006 had it and I'm just not familiar enough with this truck yet to fully grasp what it is.   Anyway, my apologies for the vague and all over the place post.  This truck is new to me, and it's been four years since I drove my 2006.  With 200k miles, I know I'll need to learn this truck quickly to avoid having any major issues, despite being confident it's got much more life to it.  My 2006 had nearly 320k on it when I parked it (nearly 300k of which I put on the truck), and it was still drivable then, though I suspected the head gasket might have blown.  I'd hoped to have that truck back by now, but it's gone forever, as I detailed in my reintroduction thread.  
    • I always drive in Sport mode. With more driving, I am finding the initial response when accelerating is much quicker now🖕 Lou
    • Is it an optical illusion in the pic or is the truck really squatting that much horribly?
  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...