Throttle over-response?

So, I've had an issue with throttle response (I think), when in reverse.

1st time: I was backing uphill to hook my trailer. Slowly squeezing the gas and it eventually jumped backwards.

2nd just backing into a parking spot and it jumped backwards.

I think what is going on is that the computer is not moving the throttle plate as I squeeze the gas pedal until it finally does and is opening too much.

Anyone notice this? @OVTune is this something you see in the program?

 

Yes.

 

You're sure it's not the increase in idle from steering input??

 

Are you asking OV Tune because you have it or because you’re seeking his expertise on the throttle mapping?

I’m assuming you aren’t turning the wheel when you are doing the above? In other words, it is different from the well-documented surges that come from the power steering (when you are moving at low speed and crank the wheel over), right?

 

Or AC cycling

 

I have probably gotten used to it somewhat, but
for backing up a hill with a trailer, etc... I use 2 Lo mod

 

Don't think so, but I can try to isolate it.

Asking OV Tune because they would know if there was a notchy throttle response.

I wasn't cranking the wheel.... I was trying to line up the hitch and ball, but they were pretty close when it happened.

Will check.

 

All it takes is a small bump in the wheel. Let us know!

 

This is an issue with the throttle mapping. On stock it takes about 5-6 percent pedal before the throttle starts to open more from its neutral position. It can be tweaked in VFTuner but I havent been successful in getting it to be 1:1 that low in the pedal range yet. If you have VFTuner its possible to tweak it so that in reverse its more gradual but there will still be a threshold from pedal to throttle input.

 

Cold or warm engine? My 17 is very much like a bucking bronco when cold when talking throttle response but once warmed up she’s a kitten.

 

It sounds like you were doing this at low speeds / near idle? If so, the ECU has an anti-stall function that will add throttle if it detects the revs falling below idle. There is a thought that this function may be preventing the DFCO fix from working in 1st gear for the tuned MTs.

I found this PID in OBD Fusion, when the revs drop below idle, the number goes in the positive direction and the ECU takes the wheel. I can hear it firing off when moving my Taco around in my garage using only the clutch.

 

Come to think of i may have when stopped at a light. Seems lately i just give it the normal about of go petal to proceed, and the truck jumps like i nearly floored it. Only happens very very seldom, and when the truck isn't fully warmed up.

 

It's at very low rpms. I'm trying to control speed backing up and all of a sudden it lurches.

Happened warm or cold. I'll try the suggestions when I get a chance.

 

I brought this up in a post awhile ago and it went no where. The idle load control programming is shit. I've never had a vehicle with large swings in idle RPM just from touching the steering wheel or the A/C compressor kicking on. It's more than normal, but all Toyota does is deny there's a problem

 

I tried the AC and steering stuff..... it wasn't consistent. I might need to try a steeper grade.