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TxShark New Member

TxShark

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I have a 2020 GMC Sierra 3500 Duramax with about 94k miles.  I am having an issue that is intermittent.  I took it to the shop and they could not reproduce it.  The issue is it shudders/stutters RPMs from sitting at a stand still to accelerating  on the roads to cruising down the road at highway speeds. The RPMs drop slightly and you can feel it in the engine like it was going to die but is oh so slight.  Some days it is very noticeable, sometimes it is very often and sometimes rarely.  No CEL's also.  It died 1 time at a stop sign but immediately cranked back up.  I am not sure what is going on, anybody run into this and found out what is causing it.

Major Tom Enthusiast

Major Tom

Posted
Posted

I have 2020 3500 also, but have not seen your problem on my truck.  I'd check the fuel filters and try some fuel injector cleaner before taking the truck back to the shop.

TxShark New Member

TxShark

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On 4/29/2026 at 4:37 PM, Major Tom said:

I have 2020 3500 also, but have not seen your problem on my truck.  I'd check the fuel filters and try some fuel injector cleaner before taking the truck back to the shop.

I have done both and still did not fix the issue.  Shop had it several days last time and could not get it to reproduce.  On the way home it did it...Shoot me!

newdude Senior Enthusiast

newdude

Posted
Posted
On 4/28/2026 at 11:13 PM, TxShark said:

I have a 2020 GMC Sierra 3500 Duramax with about 94k miles.  I am having an issue that is intermittent.  I took it to the shop and they could not reproduce it.  The issue is it shudders/stutters RPMs from sitting at a stand still to accelerating  on the roads to cruising down the road at highway speeds. The RPMs drop slightly and you can feel it in the engine like it was going to die but is oh so slight.  Some days it is very noticeable, sometimes it is very often and sometimes rarely.  No CEL's also.  It died 1 time at a stop sign but immediately cranked back up.  I am not sure what is going on, anybody run into this and found out what is causing it.

 

 

Find the bad fuel injector(s).  L5Ps love fuel injectors and the connector at the injector.  

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