3.0 Duramax cranks but won’t start

[Dbersuch]

Bought a 2021 Sierra with the 3.0 last week. Twice when trying to start the truck the starter engages and cranks the engine but it will not fire. Starter times out after a few seconds and stops cranking. Anyone else have this happen? 570 miles on the truck.

[20SierraL8T24]

Could be a lot of things. If I were to guess, it's loosing fuel pressure somewhere. Check for leaks and go from there. Intermittent issues are tough because they coincidentally never arise when the dealer has the vehicle.

[Samsil]

Same thing happened to me yesterday(2021 gmc sierra 3.0 duramax), stopped at the post office for a few minutes, got back on the truck pressed the button and it kept cranking for almost 20 seconds until it timed out. Tryed it again and it fired right up the 2nd time.

[TylerM]

Same here, 600 miles on the truck. First time

it Happened it started shorty after. Last time after being unsuccessful and waiting for roadside for about an hour i decided to pull the leads of the battery. Waited about 5 mins reconnected and the truck fired. Going back to the dealer on monday.

[Gruggas]

Had this exact situation happen to me. Dealer told me it was part of the harness relating to Cam Shaft Position Sensor. Waited a week. Dealer Said they fixed it. This was at 280km. Just happened again 2 days after getting the truck back at 450km. Will keep people updated on what happens!

[pascal cummins shoptech]

Samething for me 2021 gmc elevation 3.0 duramax. Try remote start and crank for 20 seconde press stop on keyfog and stop cranking,  retry start 1/4 turn, and ride in town after with autostop and always restart easy i tink its in keyfog signal of something ......

[Gruggas]

Hey everyone with this similar issue. I have an update. So the dealer though it was a new ECM. They threw a new one at it. Problem persisted. They now believe it’s the ring on the camshaft. Out the engine comes to replace it... might be time for lemon law.

[hesaw00]

I had this issue yesterday at about 2700 miles, had to tow it to the dealer.  This happened when i tried to crank the truck from inside the cab, pushing the ignition button.  Earlier - once about 1k miles and again about 2k - i tried to crank using key fob and had the same experience.

I am not happy about this and hate to hear that its happening to multiple trucks...especially if we are talking about cam sensors or worse.

[MNJoel]

Same here, 2021 HalfMax AT4... happened twice now... once at 200 miles and again at 650 miles. Cranks for 15-20 seconds. 

 

Super annoying. 

[Gruggas]

I’ll keep you guys updated. Since my last post, truck is still in the dealer. They tried the new ECM. No go. They had to remove the cab and the timing cover because they said there may be an issue with the timing ring on the camshaft. Hopefully I’m just this unlucky and you fellas don’t need to get to this point. I’ve asked for another truck but currently there is a shortage of trucks here in Canada.

[Ahearn35]

Same thing happened to me today for the first time at 4029mi.  Crank timed out, I got out checked for any blatant leaks, saw none, tried again and it started right up.  

 

Other issues I've been having are a engine light for abs system (only experienced one during heavy rain) and camera system wouldn't work one day. 

 

Bought the truck a month ago and I love it, I'm just nervous about the issues it's been having... All intermittent and seem to be electrical.

[Jmartin2]

Same issue since around 600 miles. Currently have around 2200 miles now. I’ve spent countless hours on the phone with my GM senior service advisor (which is a total waste of time). Will be scheduling an appointment with the dealership, however I’m not expecting a resolution to come. My truck throws no codes and always starts fine on the second attempt. I just hate how everyone I talk to wants to act like they’ve never heard of this problem when the same thing is happening on the gas 1/2 tons. I’ll try to keep everyone posted. 

[Storti]

I picked up a 21 GMC Sierra AT4 a month ago and the crank no start issue happened with 300 miles on it and now with 1100 miles on it. Second try it'll start, as of now, this might change but who knows at this point.

 

Now GM, just think if this happens at an intersection with the tree hugging auto engine off feature engaged and causes an accident.   

 

Doesn't sound like anyone has had luck with this issue yet and I'm sure GM has no clue either, they'll probably say it has covid. Anyway I will be monitoring the thread, Thanks for reading.

[RoadGlideSully]

Same thing happened to me at around 200 miles.  Drained the batter cranking (several tries).  Took it to the dealership and they replaced the battery.  Happened again at around 600 miles.  Battery held up this time but it was consistent problem for about 5-6 tries.  Waited about 15 mins (after calling a tow truck) and it started right up.  Took it to the dealership and it threw no codes and and they of course couldn't replicate it.   Hasn't happened since.  I'm now a bit leery about having found this thread and knowing several others are having a problem.  Hoping now there may be a recall in our future once they figure out what the hell is happening. 

[Greenman27]

I have a 21 Silverado with 3.0 duramax. Same issue happened to me 2 days ago.  Hit the button to start cranking and no fire.  Held the button to stop the starter waited a few seconds tried to restart and fired up like normal.  Truck is 2 months old with 1500 miles.  Will report back if and when it happens again.  Hopefully GM will have a fix soon.