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Posted
On 6/1/2021 at 2:55 PM, Dogdad said:

Any more issues since the floor mat correction? 

Ever since I noticed that, have had ZERO no-start issues

Posted

Brandon C any further issues since the bulletin fix reprogramming the ECM?

Posted (edited)

I’ve had my 2021 Sierra Denali for 3 weeks and have 900 miles so far. The non start issue has now happened to me twice so far. Have an appointment Wednesday at the dealer. Hoping it’s as easy as flashing the ecm. 
 

reading the other thread of the camshaft position sensor exciter wheel doesn’t sound like a fun fix having the truck taken apart. 

Edited by PandonSF
Posted

My 2021 Silverado is having the same issue. This is the third spell. It will turn over and keep turning over. Won’t fire up. When parked for 20 mins or so it usually restarts fine. I have paid a ton of money for this truck and I expect it to start on time, every time. Can someone please post the solution so I can relay that information to my dealership, since they can’t seem to figure it out. Please and thanks. 

Posted
1 hour ago, ABoothe said:

My 2021 Silverado is having the same issue. This is the third spell. It will turn over and keep turning over. Won’t fire up. When parked for 20 mins or so it usually restarts fine. I have paid a ton of money for this truck and I expect it to start on time, every time. Can someone please post the solution so I can relay that information to my dealership, since they can’t seem to figure it out. Please and thanks. 

If you read this thread you’ll see that No one can post the solution because it isn’t clear. Plenty of speculation and potential causes but no smoking gun at this time. 

Posted

Silverado’s for the last few years have left the factory with packing grease on the motor instead of shipping with oil due to epa regulations, the dealer is responsible for stripping excess grease upon receiving it at the lot. Sometimes the mechanics tasked with getting this grease off the motor are less than thorough. While the engine runs and heats up it makes the grease thin and runny causing it to basically get blown all over the place by the fans and belts and can get on electrical connections causing power to not get to where it needs to go, ie vehicle turning over but not starting right away. Sometimes the engine light will come on temporarily because the vehicle computer knows something wasn’t quite right but won’t give a code because it doesn’t know what’s going on and eventually goes back off after starting it up successfully a few times

Posted
2 hours ago, Jct89 said:

Silverado’s for the last few years have left the factory with packing grease on the motor instead of shipping with oil due to epa regulations, the dealer is responsible for stripping excess grease upon receiving it at the lot. Sometimes the mechanics tasked with getting this grease off the motor are less than thorough. While the engine runs and heats up it makes the grease thin and runny causing it to basically get blown all over the place by the fans and belts and can get on electrical connections causing power to not get to where it needs to go, ie vehicle turning over but not starting right away. Sometimes the engine light will come on temporarily because the vehicle computer knows something wasn’t quite right but won’t give a code because it doesn’t know what’s going on and eventually goes back off after starting it up successfully a few times

This is just stupid.  Nobody packs grease on either the inside or the outside of the motor for shipping.

Posted

JCT89

What info made you believe this is true? 

Unbelievable.

The problem IMO.

 

Head up your ass jpeg.jpg

Posted (edited)
6 hours ago, Jct89 said:

Silverado’s for the last few years have left the factory with packing grease on the motor instead of shipping with oil due to epa regulations, the dealer is responsible for stripping excess grease upon receiving it at the lot. Sometimes the mechanics tasked with getting this grease off the motor are less than thorough. While the engine runs and heats up it makes the grease thin and runny causing it to basically get blown all over the place by the fans and belts and can get on electrical connections causing power to not get to where it needs to go, ie vehicle turning over but not starting right away. Sometimes the engine light will come on temporarily because the vehicle computer knows something wasn’t quite right but won’t give a code because it doesn’t know what’s going on and eventually goes back off after starting it up successfully a few times

🤪🥴

 

How on earth would they be loaded onto and off of shipping trucks, boats or trains?

Edited by gemarsh
  • 3 weeks later...
Posted

This happened on my 2021 Silverado 3500 gas. It did it the first time at about 1500 miles and I torqued the fuse box pins at that time and thought it was fixed. Happened again a couple of weeks ago at 6500 miles. First time hot sunny day running errands around town. Second time towing a 10,000# trailer in the rain for 200 miles and stopped for fuel. Both times restarted after 15 or 20 minutes. The second time I kept cycling the retained power by opening and closing the door and then locking it. After the 4th or 5th attempt it started like normal with no codes. Took to the dealer today for a scan and found no codes. They installed the ECM software update in the previously listed service bulletin, and also a recall on the infotainment system. Hope this is the fix. I have looked at the gas pedal thing and that is not the issue here as I have the  Z71 mats that are installed correctly and always use my right foot on the brake pedal as everything I own has that requirement. I have had a couple of times when the dash indicated the remote was not found but it started anyways so that may be a sign of where the issue starts?

Posted
16 minutes ago, MT3500 said:

This happened on my 2021 Silverado 3500 gas. It did it the first time at about 1500 miles and I torqued the fuse box pins at that time and thought it was fixed. Happened again a couple of weeks ago at 6500 miles. First time hot sunny day running errands around town. Second time towing a 10,000# trailer in the rain for 200 miles and stopped for fuel. Both times restarted after 15 or 20 minutes. The second time I kept cycling the retained power by opening and closing the door and then locking it. After the 4th or 5th attempt it started like normal with no codes. Took to the dealer today for a scan and found no codes. They installed the ECM software update in the previously listed service bulletin, and also a recall on the infotainment system. Hope this is the fix. I have looked at the gas pedal thing and that is not the issue here as I have the  Z71 mats that are installed correctly and always use my right foot on the brake pedal as everything I own has that requirement. I have had a couple of times when the dash indicated the remote was not found but it started anyways so that may be a sign of where the issue starts?

Recall on infotainment system??

Posted
On 5/14/2021 at 9:06 AM, Jmartin2 said:

Anyone experience a permanent fix with this issue? My truck has the 3.0 duramax and I’m wondering if it’s potentially a different issue. Almost seems like the truck isn’t getting fuel while attempting to start. Always stars on the second attempt and never throws a code (which makes it real fun when dealing with technicians). 

I have the 3.0.  It has happened to me 7 times within the first 5k miles.  Been to the dealer 3x.  Last time they claimed to have re-torqued the fuse box bolts.  Other than that they say they can't replicate and usually mention that they "checked all the software".  First new truck i've bought in a long time so its very disappointing performance from a $60k truck.

To recap what my truck is doing
First two times, i was using key fob, and the start would spin but not fire.
3rd time - starter spun but would not fire, then it would not crank after at all for multiple attempts.  I had it towed to dealer but it actually did crank as he was putting it on the tow truck.
Times 4 - 7, push the crank button on dash, starter runs for ~10 seconds but no fire, and I can't get it to stop.  Then it has crunk on 2nd attempt every time.

Posted

This is being discussed in detail in the 2020 HD forum on this site. There is currently no fix for this problem, even after having the entire truck torn apart for the camshaft bulletin.

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