Idle drops after coming to a stop

busta350 · June 27, 2023

I have 2021 silverado 6.2 ten speed. The problem I'm having is the truck acts like it wants to stall when coming to a stop or going over speed bumps. This started after being stopped on a hill and when I went to accelerate the truck made a loud bang under the center console. There's also a clacking noise when accelerating at times. Real problem is dealership says everything is fine. My gas mileage is down and so is power.

Bikerjon · June 27, 2023

Sure sounds like the transmission or torque converter. Try a different dealer and demonstrate the condition on a road test with a mechanic. Everything is not fine!

busta350 · June 27, 2023

I even went through GM to schedule this appointment. It's the third time I've brought it back and I keep getting told they can't replicate it or everything is fine. Crazy how this happens pretty much everyday I drive the truck.

diyer2 · June 27, 2023

No codes, no idea whats wrong IMO.

Paul Beaudet · June 27, 2023

Check for a vacuum leak anywhere downstream from the MAF.

busta350 · June 28, 2023

I really do feel like it's transmission related. This truck is really jerky at times and has a noticeable whine after driving for a bit. If going under 40 and take foot off gas it's almost like applying the break and if u just slightly give it some gas it will jerk you back into your seat. After driving for a while theres also a noticeable whining sound.The dealership said they are gonna drive it some more but I have no faith they will find anything.

Edited June 28, 2023 by busta350

Bikerjon · June 28, 2023

Check your transmission fluid. Does it smell burnt? Wipe the trans. dip stick on a white paper towel or shop towel, if the fluid is clean thats a good sign. If the fluid is black or burned this points to worn clutch packs, overheating or other transmission damage. Do you keep taking your truck back to the same dealer who cannot verify or fix the problem? Have you road tested and demonstrated your complaint with a Certified Automotive Technician? I would bring your truck into a Dealer or A.S.E. certified mechanic who knows what they are doing and get your truck fixed. It seems like you are wasting your time with your dealership that cannot diagnose a drivability issue.

busta350 · June 28, 2023

Looks like I'll be having to take it to another dealership. Losing faith in Gm being able to find anything seems like they only know how to check for codes. This problem happens to me everyday but apparently not when it's at the dealership.

jaxcam02 · June 30, 2023

On 6/28/2023 at 5:43 PM, busta350 said:

Looks like I'll be having to take it to another dealership. Losing faith in Gm being able to find anything seems like they only know how to check for codes. This problem happens to me everyday but apparently not when it's at the dealership.

Make them get a tech to ride with you so you can duplicate the condition. Stop dropping it off.