Hi everyone! I’m new here, and very happy to be apart of such an amazing community! I’ve referred to the Forum a lot but never joined the community until now.

I have an 07 H3, with 163,000 miles. Regular maintenance to keep everything up to par, happy and healthy. The only thing I question, is why does my Hummer almost push, or jolt a little when I go over 45 mph?
I’m not the best at explaining things but hear me out. Imagine you’re walking and someone else is behind you. Every now and then they just give you a little shove to push you a little faster / further. That’s the best way I could explain, it’s not like a death wobble or anything like that. Not shaky, just a little jolt or push forward. It’s intermittent too which is the icing on top of the cake.

I got my check engine light code read today, popped up with P0420, P0442, P0353, P0741

Not sure if any of these codes would be the answer or at least a clue to my problem, so I figured I’d join the group and ask here while doing some outside research myself

Sorry this is so long, I appreciate any help and advice so much! Thanks a bunch!

 

P0420
https://www.hummerforums.com/forum/p...20-code-33223/

P0422
https://www.hummerforums.com/forum/h...7/p0442-26131/

P0353

P0353 code are bad ignition coils, ignition coil control circuit issues, outdated PCM software, or PCM failure.

P0741
https://www.hummerforums.com/forum/h...d-p0741-45169/

 

Not sure exactly what you are saying by "when I go over 45 mph", but that makes me think of the torque converter. Transmission fluid at correct level and in good shape?