Acceleration bogging down

https://youtu.be/zGOJynrbcm0

Ok everyone. I put my foot straight to the floor and this happens.

Stock intake, ovtune software.

Thoughts?

 

transmission programming. Would normally want to shift right there but the hard acceleration wont let the computer do it so it shudders for the split second because it the computer essentially had to tell itself to down shift (although no physical shift occurred). Less noticeable with ECT on because the shift point is moved higher up in the rev range.

 

It really wants to shift that early?

I'm talking about the stutter at 1500rpm where the to rpms drop back to 1000 and then bounces back up and down.

I lifted off the gas at 4500rpm

 

yes. In a gentle acceleration it would. The transmission in these trucks try to be in the highest gear possible for fuel efficiency. its what leads to the gear hunting a lot of guys on here complain about. If you drive with a heavy foot maybe look into the ECT always on mod.

 

Not while its floored it won't upshift for economy.

I'd reflash to stock and disconnect the battery and discharge it if it were mine.

 

it wont but it wants to. thats what the hesitation is. its an attempt to upshift or at least its checking to see if it could.

 

Disagree 100%. Mine doesn't do that. The truck won't upshift or try to like that with it floored.

To me it looks like the wheels are slipping then gripping. The video has a strange sound in at launch that could be the tires, could be something else.

 

Absolutely no tire spin.. and traction control is 100% turned off

 

Yeah I can see the Trac Off light is on. Did it always do this or is it new?

 

I've had the truck for a year and never mashed it to the floor it from a stop until the other day...

 

I don't make a habit of it myself, trying to beat my highscore on MPG, but my truck doesn't do anything like that video. Have you tried flashing back to stock?

 

Just refreshed to stock so we'll see in the morning..

 

Truck is flashed back to stock and this doesn't happen any more...

 

Off to the OV tune thread then.

 

I shot this over to OVtune directly and said he's going to try and replicate on his truck. Again.. Great service from Mat!

 

I'm sure he will get you straightened out.

 

So update on this - Stock tune loaded - stock intake installed. Stumble/whatever you want to call it still happens.

I took it to the dealer and they tried to diagnose it and recognized that there is an issue but didn't comment on what it could be. They asked me to bring the truck back and leave it for a few days.

Per the tech's notes on my service ticket the truck "falls on its face during acceleration"

I also went ahead and replaced the Crank Position Sensor (no changes) and did the Zero Point Calibration (no changes). My opinion is that this is something in the programming since if I roll on to the throttle this doesn't happen and the truck takes off perfectly fine.