GEN 2 Rolling start, floor it, and it falls on its face

[clark98ut]

I've had an issue twice now where I am cruising along at 10-20mph, I floor it, and it stumbles. Almost feels like missing a gear in a manual transmission car. I let off the gas, and everything is back to normal.

This has only happened at WOT...1/2, 3/4 throttle, never an issue. I believe one time was pre-mod, and one time post-mod. Any thoughts?

Current mods include Gearhead Tune, CVF Intercooler, S&B CAI, AWE 2FG, MBRP Resonator Delete.

 

[TXRaptor]

If you had said post mod only, I would think it was tune related. Have you changed out your spark plugs for colder ones?

 

[clark98ut]

If you had said post mod only, I would think it was tune related. Have you changed out your spake plugs for colder ones?

I have not. I have them at the house, just haven't got around to it yet.

 

[TXRaptor]

You are obviously past the point of taking it into the dealer for warranty work, so you might as well try the colder spark plugs.

I have the Full Race IC, MPT Tunes, FlowMaster Muffler, 170 tstat and SP542 spark plugs in my 2018. It runs fantastic in all modes and I have never experienced any stumbling. You can also try removing the tune for a while and see if it stumbles again to eliminate it as the cause. The next thing would be the CAI.

 

[smurfslayer]

I believe one time was pre-mod, and one time post-mod. Any thoughts?

Never mod a vehicle with a known or suspected problem because troubleshooting becomes several times harder.

When you floor it, from what gear are you downshifting?
can you replicate in manual mode?

 

[Badgertits]

FWIW I’ve had this happen to me also & I also have a GH tune. Happened a couple times to me after driving normally for a bit but getting on it relatively soon after a cold start (trans temps in 160s+ tho) - I actually had the SCT programmer plugged in & datalogging one time it did it I just haven’t had the time to reach out to GH & send files.

My best basic guess is that the tune is asking the truck for more boost than it was able to muster at the time & went limp to prevent any issues, after getting On it a few times @ partial throttle WOT was fine. I also think it may be a brain fart by the ECU/TCM pulling torque to the wheels if the truck isn’t completely warmed up or something, like an exaggerated fail safe built in?

I had read other people having the same issue stock but seems more relegated to tuned trucks.

I have a feeling something to do w/ boost - I was/am running fairly fresh SP542 plugs gapped @ whatever MPT ships em

one last thing I’ll mention- it certainly didn’t feel like there was any damage/excess wear occurring as a result, it was such a “smooth” seamless drop in acceleration it almost felt factory- no codes thrown that I know of either.

 

[clark98ut]

one last thing I’ll mention- it certainly didn’t feel like there was any damage/excess wear occurring as a result, it was such a “smooth” seamless drop in acceleration it almost felt factory- no codes thrown that I know of either.

Yeah, it doesn't feel like anything really bad is happening...like I said, the best comparison I have is to missing a gear in a manual vehicle.

As for being cold, the most recent time this happened, I had just driven 2.5 hours, so it was definitely warmed up.

 

[Badgertits]

Yeah, it doesn't feel like anything really bad is happening...like I said, the best comparison I have is to missing a gear in a manual vehicle.

As for being cold, the most recent time this happened, I had just driven 2.5 hours, so it was definitely warmed up.

will either way I’ll report back what I found out from GH

 

[clark98ut]

will either way I’ll report back what I found out from GH

Sounds good. Appreciate it!

 

[onthebrake]

I've had an issue twice now where I am cruising along at 10-20mph, I floor it, and it stumbles. Almost feels like missing a gear in a manual transmission car. I let off the gas, and everything is back to normal.

This has only happened at WOT...1/2, 3/4 throttle, never an issue. I believe one time was pre-mod, and one time post-mod. Any thoughts?

Current mods include Gearhead Tune, CVF Intercooler, S&B CAI, AWE 2FG, MBRP Resonator Delete.

Are you sure it happened pre-mod ? You REALLY need to change your plugs yesterday considering the tune and intercooler upgrade.