Throttle dead spot issue

[Gabe]

Hi guys,

Just joined, hoping somebody might be able to throw some light on what's going on with my car.

I have a good tuner working on it, he's done hundreds of Mustangs and is regarded in the area as THE Mustang guy.

My set-up:

2013 Mustang GT 6-speed, 2.3L Whipple supercharger, ID1000 injectors, GT500 twin 60mm throttle body, JLT BigAir Cold-Air Intake. Stock cat converters, exhaust manifolds.

Car drove perfectly on the previous tune, naturally aspirated, with a different intake kit on it and no other mods.

Supercharger kit and everything else above now installed, tune uploaded, have a throttle dead spot at the top of the gas pedal.
The first 1/4-1/2" of travel does nothing, then I get more throttle than I expect.
According to the tuner, the throttle Position Sensor values don't change at all during that dead spot, when he looks at them on his laptop.

Thinking possible bad throttle body, but a few people have now told me "it's the tune", quoting things like "commanded torque tables" and "tip-in adjustment".

Anybody have any thoughts?

Tuning is done on a Dynojet via SCT software


Thank you in advance ...

[Eric@HPTuners]

This is a complex topic. Without looking at this tune, I can't offer much insight as to the cause. My educated guess is that it is in the tune though.

[Gremlin85]

Gabe, glad to see you made it over here.

Eric is the one handling everything Ford here. If he doesn't know off hand, then it's going to be up to your tuner to get it resolved. Unless there is a way to upload the tune and possibly a data log for us to see.

[Gabe]

Thanks guys, I went back today and still no go. Tried another throttle body and you can see it not move for the first bit of pedal travel, then it jerks open, same behavior as the new Tb that came with the Whipple kit.

The tuner says the Throttle Position Sensor reads something like 4.1-4.3V at idle, which apparently is what it should read at WOT?

I don't know but I'm frustrated, the tuner's frustrated, this sucks

[Eric@HPTuners]

Thanks guys, I went back today and still no go. Tried another throttle body and you can see it not move for the first bit of pedal travel, then it jerks open, same behavior as the new Tb that came with the Whipple kit.

The tuner says the Throttle Position Sensor reads something like 4.1-4.3V at idle, which apparently is what it should read at WOT?

I don't know but I'm frustrated, the tuner's frustrated, this sucks

There are very few tuners that have a handle on tuning these cars.

[c.u]

Get a stock file load the injector data in then flash. If the TB works then its the tune,if it dont then its in the car itself.

[JVK]

Maybe get someone to read the tune with HP and then post it up so other ford tuners like Eric can have a look for you.

[Gabe]

Thanks guys ..... if I were to datalog, is there anything in particular I'd have to do?
I haven't datalogged with an SCT before, only with the Diablosport tuner I had for my '07 Charger, and that tuner makes you pick certain pids to log.
Is the SCT the same or does it log everything automatically?

The tuner said he couldn't datalog it last night. We tried another throttle body and it was doing the exact same thing. As the pedal was slowly applied, it would do nothing during that dead spot, then jerk open. The tuner said he's seeing 4.1-4.3V from the TPS at idle. He thought this would be the WOT value.

I left stumped/frustrated, and with a car that still drives like crap.

One additional SCT-related question: can I hook it up to my laptop and save the tune from the tuner onto my laptop?

[Gremlin85]

With HP Tuners, we are still unable to data log the Copperhead ECU. At least from the Beta version I have.

I am not familiar with SCT or Diablo so I am unsure how to datalog with them. Where did you purchase your SCT device from and who did the base tunes? I would contact them on datalogging.

If it's not the TB and you tried 2 of them and it does the same thing, I would look into the tune. Like what was mentioned over on S197Forums, the tuner had a small chance to adjust one of the 36 tables for Commanded Torque. Have the tuner look back into those to check if one was accidentally set to all zero's. Maybe a pinched wire in the harness or the connector on the harness side has a fault in a pin or a connection???

Tuning a custom setup can be very frustrating if theres no help to work from. Having to pioneer a problem is a huge undertaking but sharing with the community can make it easier for the next guy. I hope your tuner can find the solution quickly.

You should be able to save the file that's already on there using HP Tuners. I am not suer how SCT would work but I ASSume it could.

[ElecTech]

With HP Tuners, we are still unable to data log the Copperhead ECU. At least from the Beta version I have.

2.24 should be able to datalog the Generic SAE PID's.

[caniggia]

Put stock tune in and look how throttle works without starting engine. If it works good, it's tune related.

[Gabe]

Put stock tune in and look how throttle works without starting engine. If it works good, it's tune related.

Will that work with a GT500 throttle body when the car is running a stock GT tune?

[caniggia]

Yes

[Gabe]

Well, ended up ordering and I'm now running a JDM e-mail tune.
Throttle issue gone, throttle now as linear as stock, just with a much beefier response from the engine

Going back to the dyno today to find out numbers and maybe do a datalog ...