Jherrera30

Hello new here just wanted to know if anyone has had any issues with motor mounts on the 5.3L. I have a 2018 suburban and it idles rough only on drive if I rev it up the slightest and hold it goes away. Like the title says i have no misfires while looking at live data.

repairman54

Power braking and watching motor movement would show a broken mount.
Cleaning throttle body of carbon built is is one thing to do, several doses of fuel injector cleaner is another.
Close to 100k miles then it's time for plugs, worn plugs will affect idle.
Fuel trims should be running between -5 and + 5 .

hanky

Can you post the data so we could look at it?

Jherrera30

Thanks for the reply guys I have tried seafoam carbon cleaner and replaced all plugs and wires as well. It has 85k miles and when I get a chance i will post data as well.

repairman54

Did you use AC plugs ?
I mistakenly put NGK's in my '11 and it had a rough idle, Pulled them out and with the AC plugs it was smoother.
I always use NGK in my powersports motors with great results so I figured I'd try them, my 5.3 didn't like them. Even though I used the spec'ed plugs the NGK had less of a protruding tip than the AC's.

hanky

Ever wonder what the engineers and research people do for an auto manufacturer?

They spend hours, days testing all sorts of combinations of which will work best under most conditions and that is how they come up with what should work best in their product. Had to learn that the hard way. Grant you some aftermarket parts from reliable manufacturers are equally as good and can be sometimes better, but I have found staying with OEM when possible , paid off.

KChevy75

Sounds like your typical 5.3l GM engine.