Jump to content
  • Sign up for FREE! Become a GM-Trucks.com Member Today!

    In 20 seconds you can become part of the worlds largest and oldest community discussing General Motors, Chevrolet and GMC branded pickups, crossovers, and SUVs. From buying research to owner support, join 1.5 MILLION GM Truck Enthusiasts every month who use GM-Trucks.com as a daily part of their ownership experience. 

Recommended Posts

I have a 2014 Silverado LTZ, with a 5.3L engine. There is approximately 145,000 miles on the engine. I have a misfire on the #3 cylinder. I have replaced the induction coil on the #3 cylinder, but I still have a misfire on this cylinder. My mechanic says that the lobe on the camshaft is worn and the camshaft needs to be replaced. 

I would think that if the lobe on the camshaft is bad then other lobes would also be bad, a defective camshaft.

 

Has anyone else had this problem? Does anyone have any suggestions as to what might be causing the misfire.

 

Thank you in advance for any advise the you can provide.

Julian.

Link to comment
Share on other sites

2 hours ago, jwroch said:

My mechanic says that the lobe on the camshaft is worn and the camshaft needs to be replaced. 

I would think that if the lobe on the camshaft is bad then other lobes would also be bad, a defective camshaft.

 

 

 

Nope.  That just means cylinder 3 had a lifter probably spin in the lifter bore or in the lifter retainer and then pounded away at the cam lobe.  

 

Swap a wire, swap the plug.  If it's still there, compression check.  I'd then maybe pull the rocker cover and pull the pushrods and valve springs out, see if they are bent/broken.    

 

Also, only because I've seen it happen.  Cylinder 3 is on the driver's side, second from the front of the engine.  So if you are leaning over the driver's fender looking at the engine bay, cylinder 1 is closest to the radiator, 7 is all the way at the firewall.  

Link to comment
Share on other sites

  • 2 weeks later...

Problem with injector swap is.  You have to pull all the injectors on that rail at the same time.  Then put all new O rings back onto each injector.  And that is a huge pain in the ass.  I've done it a couple time on my truck.

 

If want to go that route let me know and I have a really good video saved on how to do the seals without any speacial tools.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

  • Similar Content

    • By The Pig Dusters
      Okay guys I bought this truck from a dealership in September. It was used and I got a 30 Day warranty. After the 30 day period, this is what’s happening. I got in my truck and noticed a rough idle. My truck would shake and out of no where the check engine light starts flashing and my traction control light comes on. I took it to my buddies and we got a P0308 Misfire Detected Cylinder 8. So I did some research.. I also had a code which was P219B. Air/fuel mixture ratio. 
       
      I changed the spark plugs.. didn’t work. I moved coil packs.. the misfire didn’t move. So we watched Live data on the scanner and injector 7 was acting up. So we replaced all the injectors on that side and this truck is still missing.. I’ve ran seafoam through it and cleaned the throttle body and MAS.  My buddy things I have a valve issue or something wrong with the cylinder…
       
      there is no AFM deleted or anything of that sort. The truck has worked flawlessly until now. 135,000 miles on it. The rocker arms all
      looked great.
       
      please someone give me something to try. I just want my truck fixed lol.  
       
      posting a link below of what it’s doing…

       
       
    • By kevin camps
      driving a 97 k2500 camper special, 4l80e with 454 vortec
       
      couple days ago I got in my truck after work and noticed it would stumble when hot, 100C no problem but a little bit warmer and i would have issues. always under load during acceleration. got home and idled in drive and it felt like an obvious misfire, RPM would drop to about 500. pop it in neutral or park and no misfire or stumbling, its been confusing me since in the mornings when i pull it out the garage it has no problems all the way to work (5 minutes highway and 5 minutes city) but end of the day and evening- same issue
       
      bought the truck with 268km now has 276, oil change every 5000k.
       
      did fuel pump (48psi at idle now) FPR, distributor cap and rotor, plug wires and plugs, ran seafoam through the intake and in the fuel tank.
       
      ive heard of distributor gears going south but id assume then i would have the issue when cold too. runs like a top at any temp below 100C, no engine light, plugged the scanner in anyways and no codes whatsoever.
       
      any help is appreciated, looked through forums for a couple days now but nothing exactly like what I'm experiencing.
       
      kevin,
    • By Jerome Leberer
      Hey guys and gals,

      Long time creeper, first time poster. I currently have a 2011 silverado 1500, with 163,622 miles on it. It's a 5.3 vortec engine. It smokes from the exhaust a light blue exhaust that's mixed with a grey/white exhaust. It stops smoking after roughly 10 seconds of running. Haven't noticed it while driving. It also doesn't smoke every start-up. It rough idles when in park. I replaced the plugs and wires a couple weeks ago, and I started misfiring on cylinder 8 after the change, before the change it was cylinder 5. The only codes it's thrown is for the misfiring. I also pulled plug 8 after the codes to check it and found oil on it. I did a combustion gas leak test and the liquid stayed the same color (blue). I'm starting to lose my mind. Any thoughts, suggestions to try? Also, as of now....I've noticed no loss in power at the moment.
    • By Leslie Politron
      Hi. I bought a new 2021 AT4 March 5. 20 miles on it. Drove home from the dealer (4 miles) and the next time I turned it on, CEL and OnStar diagnostics emails me to take it to the service department. They say they reset MAP sensor and send me on my way. Later that day, same thing happens. I take it back in, they say MAP sensory needs replacing. They had it almost 2 weeks waiting on the part. After they replaced it, everything went fine for about 1200 miles and then I get blinking CEL for about 30 seconds then it stops. Next day, blinking CEL for a minute or so, and then it turns solid. I took it back to the dealer and they say the only code pulled was P0300 misfire. They have no idea what’s causing it, and quite frankly I’m pretty fed up at this point. They’ve had my new truck longer than I have in the month I’ve owned it. Has anyone had something similar happen?

    • By Ryan Forth
      First time posting but have searched the forums for years and have always found what I needed. Well this time I'm stumped, so I have a 1994 gmc k1500 pickup with a rebuilt 350 tbi bored .030 out with a stage 2 cam and long tube headers. (About 4000 miles on engine.) new distributor, plugs, wires, vss, 
       
      So here's what's going on, the speedometer jumps around super erratically but when I turn the heater on it seems to change how much the speedo jumps around. If its on high it jumps around the least. Low or off its just bouncing off 85mph like bouncing to the point I can hear it slamming into whatever stops the needle from going any further. When I turn the turn signal on left it makes the radio light dim with each flash. The odometer turns constantly when while sitting in park. I have replaced the vss at the very end of the trans where the rear drive shift meets. I was drive the other day and the truck just didn't want to move seemed like it was just constantly back firing or misfiring. I have been trying to check all the engine grounds but not sure what all needs to be grounded. Any info/advice would be greatly appreciated. 
  • Recently Browsing   0 members

    • No registered users viewing this page.
  • Forum Statistics

    241.5k
    Total Topics
    1.4m
    Total Posts
  • Member Statistics

    305,853
    Total Members
    8,960
    Most Online
    ClearlyDigital
    Newest Member
    ClearlyDigital
    Joined


×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.