Runaway Throttle-Only in park/neutral

[Charles P.]

Hey everyone,

Running into an issue with my truck and I want to see if anyone can give me some insight.

2017-6.2l-4wd

 

Truck drives normal in drive. Throttle response is good, gets up and goes, But, If I put it in park and try to rev it, it will runaway all the way to limiter and slowly creep back down. I will try to post a video a little later if needed, but I wanted to see if anyone has had this issue. It will also do it in neutral, but does not in drive.

As well, I do not have a throttle response enhancer installed.

 

Things on the truck:

UPR Catch Can Kit

American Racing Headers

CAI Brand Cold air intake

MBRP Exhaust

 

Things I have tried/done (some are unrelated to this issue):

Throttle Body replacement

MAF Replacement

Harness + Throttle body Check-over

Pedal Wiring check-over

Tune Checked by Tuner- We even put it back to OEM tune to see if anything changed

Check for engine codes

Check for irregular Vacuum amount. I wasn't entirely sure what the normal vacuum amount should be, but it "looked" okay.

 

Overall the truck is pretty clean in the sense of being able to "see" anything wrong.