2021 GMC Sierra 1500 Vehicle speed control Problems

“Dashboard keeps returning to aljarir type writing. We bought it with American English but won't stay in English. Monday will be 30 day and I believe the dealer is ghosting me. Y'all have any ideas how to reset the dashboard without replacing the radio??? Closest answer I was given.”

“I just took my 2021 GMC Sierra 1503.0 Duramax diesel into Faulkner Nissan, today 10/18/2025 m, to have that recall fixed. I picked it up from the dealership and drove about 10 miles before it went into limp mode and reduced power mode while I was driving and started to shift very roughly and I’ve never had any issue like this before they supposedly fix this recall, I think the software patch made it worse in my case. …”

“Tried to accelerate and heard a loud pop and the truck didn’t accelerate. Pretty much went idle in the middle of the road. The check engine light, the traction control light, and the ABS light all came on. I would press on the gas and it would rev but nothing would happen till a few seconds later the RPM’s would shoot up and you could tell it was trying to get going but didn’t very slowly and I would hear a clicking noise every time it was around the second gear. It put my children and myself in danger because traffic was heavy with vehicles going 70+mph merging into one lane. …”

“On the morning of 1/19/25, my 2021 GMC Sierra 6.2L AT4 went into limp mode heading south on HWY 207 in Leavenworth, WA at approximately 60 m.p.h. Fortunately, I was able to avoid a rear end collision. I quickly turned the truck off in the middle of the road and restarted it with a CEL. When I returned home almost 180 miles away, my local mechanic diagnosed a code P0303 and cleared it. Since, the truck has continued to shutter at various speeds without throwing a code. It is currently at Haselwood GMC in Bremerton, WA being scanned, recorded, and findings set to GM waiting for resolve. …”

“Dtc code p1098 present related to faulty coolant control valve on 3.0 duramax diesel engiine. This is a known issue with this engine and is supposed to be covered under the 100k mile powertrain warranty. Previously took vehicle into dealership for repair involving replacement of the coolant control valve but was told reprogramming of the ECM was required first step per GM repair bulletin. Reprogramming cost me $195 and was told this was not covered under the 100k powertrain warranty. …”