Dead Band ON Throttle

[larrybia]

I have recently (two weeks ago) purchased a 2007 GS GT and have just returned from a trip to Vegas where I put 1500 miles on the car. A real shake down cruse. There are two problems that I have noticed that I will be bringing the car back to the dealer Monday to fix. I notices the problems shortly after picking up the car and told the dealer but he said get some more time on the car to really see whats going on. Does anyone have any insight into what may be causing the problems? I would like some additional information when I talk to the dealer again. Has anyone experienced the same?

Problem one is that there appears to be a significant dead band with the throttle. I have to push down the peddle about a inch before the engine will respond. This has a significant impact on starting from a light, reversing out of a parking space, or accelerating out of a turn. It is not always safe to punch through this dead band each time I want to move out. I think the “Drive by Wire” throttle is not adjusted correctly.

Problem tow is a vibration at 1750 RPM in first. This vibration is only for a short time just before shifting to second. The vibration gets worst when the transmission gets hot and when pulling up a hill. I have the automatic.

Any comments I would appreciate.

[bigwhitecobra]

1. I don't claim to be an expert with the 05-up cars, mainly cause I don't think I like them. I love the looks, but the seating position, shifter arangement, center console, all of that remind me of a F-body, and I hate F-body's. Anyway, before I digress, sounds like you have a common problem. Even though it would at first seem like you have a problem with the throttle, it may well be with the transmission. There may be an updated software install that would get rid of that problem for you.

2. Refer to answer one. Almost confirms it for me.

[larrybia]

Is there anywhere on the web where I could get a better understanding of how software controls all the functions in the 05 and up Mustangs? After looking at some articles in various Mustang magazines it appears that a lot of the features in the software are tunable if you have the right interface hardware and knowledge. I would really like to understand what is going on and maybe experiment with different settings.

I agree with you “Bigwhitecobra” about the cockpit, but as you say the car looks great. I was 16 when the 64 came out and could only afford a Falcon. Now that My wife and I are “Empty Nesters” we could get what we wanted. We looked at the 06 GTO and Monte Carlo but just could not resist the Mustang looks. Cobra and Roach had too much HP so we got the GS GT. We got rid of a 93 SHO with 238K on it for the GT. Its probably too bad we will not drive it like it should be, but we plan to hand down to one of the grand kids when he/she is of age. It will be pristine.

Any direction on where to find technical descriptions on internal functionality would be appreciated.

[Jeff Chambers]

The 05 & up are quite complicated with the drive-by-wire controls. Most owner level software is not going to get you in to the electronic throttle control functions because of its complexity. The feed forward & feed back management of ETC is difficult to tune and even more difficult to find in-depth information on. Even at the professional level, its hard to find advanced learning materials on the logic employed.

That being said, I am not aware of any TSB's or recalls for the 07 in terms of ETC issues. There was a TSB on the 05's that called for replacing the TPS and loading a new computer calibration. What you describe would seem to be more of a mechanical issue and not a programming issue. I'd get back with your dealer on the problem and if they are unwilling to help with or solve the problems then find another dealer and also call Ford customer service to log your issue as an official warranty complaint.

[larrybia]

I just got back from the dealer. He checked over the throttle mechanical parts and found no problems. He indicated that what I am seeing is typical for a “Fly by Wire” system and was much worst on the 05s when they first came out. The difference between the feel of a cable system and a “Fly by Wire” system is significant and requires getting use to. I have heard that the “Fly by Wire” systems in the late model Corvettes and on diesel trucks also have the same feel which is annoying until you are use to it. Unlike the cable system, where the throttle plate position is where your foot goes, the position of the throttle plate for a “Fly by Wire” system goes where and when the computer wants it to go indirectly as a function of you foot. As you indicated, the function controlling the throttle plate (engine RPM/power) is very complicated. Output from the throttle also goes to the fuel pressure system and several other systems. So the software function for throttle position to throttle plate position is complicated by the requirement to control other systems. This may be an efficient design but I do not believe it is a safe design, especially for an automatic. I want the RPM of the engine and subsequently the speed of the car to be directly related to my foot position.

I will be passing my feelings and thoughts to Ford Technical and see what they think. I would hope that others feel the same annoying operation of the throttle on an 05 and above automatic, and if so, maybe we could get Ford to improve the software to make the throttle operate more like a cable system.

I would appreciate any comments and will keep this forum informed on any addition things I find out on this subject.

[larrybia]

PS My problem 2 is becaues of a problem with the Limited Slip Differential disk pack. It is being replaced.

[Jeff Chambers]

The throttle lag that you describe IS NOT typical of the 5R55-equipped cars. I've tuned and driven a boatload of these from 05 to 07. Ask the dealer to let you drive another car on the lot and see if the feeling is the same...chances are it is not and you're dealing with a problem unique to your car. Ford has gone to great lengths to make sure that the ETC provides the same driver feedback as people are accustomed to with the cable actuated throttle controls. I'd get firm with your dealer to either address your concerns or take the car back under the Lemon Laws of your state.

[larrybia]

I did test drive a second GT with an auto and I did not see any significant difference when compared to my GT. Also, both do not feel like my 93 SHO automatic I traded in for the GT. That car had 238K on it and was strong but old. One test I use is rapid pushing on the throttle pedal. With the GT there is no engine RPM change with significant depression at a fast rate. If I slow up the rate than I get the RPM change. The “Vroom Vroom” you expect. My SHO would show significant RPM change with the fast rate.

I am not sure that my testing is valid or representative. I may not know how to quantify the problem. All I know is that my GT and the other I drove do not feel the same as my SHO or other “Cable” throttle system cars I have driven. If no one else has seen the problem maybe I am being too sensitive or too gentle with the car. But so far it does not seam right to me, however, I do not yet know how to refute the dealers claims. Is there some definitive test for this situation? Do you have a RPM vs Throttle Position plot of what to expect? I am not done with this problem yet!

[bigwhitecobra]

My brother bought a 06 Charger, which is a boat, and it's a drive by wire throttle also. I drove it the other day, and noticed a lag. It's barely perceptable, but for us car guys, it's annoying. My brother didn't even know what I was talking about when I pointed it out. I had to put him in another car and let him see what I meant. It took a while....

Anyway, there are tuners out there that can tune alot of that out, but the best way to get rid of it, it to convert back to a throttle cable. It should be possible, but it may not be worth it. I would look at tuning what you can out of it, and if nothing else, keep the throttle body as clean as you can....the blade tends to stick over time....carbon build up and what not. Anyway, these are just a couple of ideas off the top of my head. I hope it all works out.

[Jeff Chambers]

The area where we remove throttle lag in tuning is on the shifts. Our tuning basically eliminates the automatic butterfly closure when the clutch is depressed. This allows you to effectively power shift an ETC vehicle. Usually worth about .5 seconds on a stock 05-07 Mustang in the 1/4 mile. Very little is done in the region that he complains of. The feedfoward logic/tables are very difficult to work with...the complexity of the logic is mind boggling.

[larrybia]

Thanks for all the advice. I may look at better overall tunning but will probably learn to live with the different ETC response. I have heard from many that thats what you get with ETC. It just seams strange that everyone accepts it. Maybe the combiniation of ETC with an automatic is the worst case. The car is an auto because I bought it for my wife!