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Discussion Starter #1
I have seen a lot of threads on various sites talking about hesitation. A lot of people have experienced it, but don't know what conditions caused it. This makes it deficult for warranty service and Ford to understand we have a real issue out here. I think I have at least a partial answer on how to make a 05 GT manual engine hesitate.

I drive a lot on weekends from Columbus Ohio to Cinci Ohio which is about 120 miles and rather flat interstate. I usually go around 70 MPH and keep my speed constant with or without the cruise control on (traction control can be on or off). If the car travels at least 10 miles and throttle position remains relatively constant, the car will hesitate once after shifting down to 3rd and the throttle pedal pushed to the floor. The hesitation is like you turned the key off for a fraction of a second. The hesitation also occurs when cruising at a constant speed and then coming to a normal stop, then attempting a hard acceleration in first. This last description is really weird. After cruising for about forty miles I stopped at a rest stop and turned the car completely off. Started the car normally and shifted into 1st. Got the car rolling at about 5 mph then tried to floor it when I hit the merge ramp. The car exibited the same hesitation. I should note that once the care hesitates it runs just fine.

Can anyone duplicate any of these findings? I would like to gather the data and present it to Ford.

I WANT THIS FIXED!!

My thanks to any reply in advance.
 

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It's the drive by wire thats doing it.You'll never complety get rid of it unless you get a tune.
Your Stang (comp)is constantly learning.
View your CD that came with your Stang it'll give you some insight.
 

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The car has torque limiters in the computer... As Rick pointed out, get a Tuner and it will fix you right up... In the words of my buddy at Ford, "We want to make sure your drive train makes it through the warranty period."
 

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Discussion Starter #4
I probably didn't make my self clear. Once the car hesitates you can shift down, do rapid starts without any hesitation at all. You must drive at a constant speed first. That would rule out any learning and/or torque limiter programing present in the computer. You should not need a tune to fix this.

Again, can any one dupicate my results?

Additional documentation/confirmation on the problem would help my case with Ford.
My thanks in advance
 

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FYI, a tune will not fix this..... My car still does this. Exact same thing happens to me on cruise and also in morning with hard accel from stop. I also have a Saleen S/C setup and custom tuning. The car has had this issue since it was new without S/C and it still has it with S/C and new tune. It's something in the base programming that a regular tune will not fix. The computer has be "Recalibrated" with a ford program, then you can tune on top of that with the tuner's setup reconfigured for the new calibration from Ford.
 

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does auto hav this problem too? this car should be punchy as hell straight off the line. why do we hav to rev to 3500 plus rpms to get any response ie spinning tires , when auto just needs to do breakstand at 2000 rpms to achieve this . damn hit the peddle and go ,right!!! .there should be no lag ,quite frustrating.computers suck. bring back cables. :sterb:
 

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vynle said:
does auto hav this problem too? this car should be punchy as hell straight off the line. why do we hav to rev to 3500 plus rpms to get any response ie spinning tires , when auto just needs to do breakstand at 2000 rpms to achieve this . damn hit the peddle and go ,right!!! .there should be no lag ,quite frustrating.computers suck. bring back cables. :sterb:
Yeah, sometimes DBW is a PITA!!!! Don't know on the auto's but I assume it would be a bit less noticable since the T/C would sheild you from some of the slack...
 

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I experienced this problem once while leaving a rest stop (after driving 3-4 hours on the highway in cruise at about 75). I shifted normally through 1st and 2nd, then hit the on ramp in 3rd and floored it. It started to accelerate normally, then hesitated for about a sec, then continued to accelerate. Ran normally afterword.
 

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The auto has the same malfunction as does the V6. Of course if you never drive on the interstate or a highway where you can cruise you'll never have a problem. Ford is either ignoring this problem or they just don't have enough info on what causes it to develope a fix.
 

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I still get it occassionally, but not as often and not as hard as the first few times it happened. I cannot for the life of me produce it on demand. Very frustrating that it can't be reproduced with a tech in the car. I'm sure Ford has heard enough complaints to look into it.
 

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nonsensez9 said:
I still get it occassionally, but not as often and not as hard as the first few times it happened. I cannot for the life of me produce it on demand. Very frustrating that it can't be reproduced with a tech in the car. I'm sure Ford has heard enough complaints to look into it.
Being a former tech, I can tell you this: If you can reproduce it by following the about scenario, and there is no TSB on it, or fault codes, all the tech can do is load the latest programming in the ECM. If that fixes it, great, if not, then you have to wait until Ford Engineers get their hand on a car, along with a tech and they will plug all their monitoring equipment into the engine wiring harness in an attempt to capture the fault during logging. Then they could isolate the issue. Just a funny thought, ones with XCAL2's could use the Laptop data logging feature to see what system, (Spark, fuel) etc is cutting out when this occurs.
 
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chuckles, this must be an anomoly in a few cars as mine has zero issues of this nature. How many owners really suffer from this?
I am really amazed this exists given the response I am getting from my mods.
 

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I'm wondering the same thing. A few of the other descriptions are exactly what I experienced, but a lot are not. I can't get it to stumble on hard accel after a run, like someone mentioned, and I can't get it to reproduce the stumble I felt at speed. Heck, it runs fine now and I can't make it stumble. The only thing I can point out is that it isn't as hot now as when it cut out. Being that the ETC is a triple-redundant computer system, a momentary lapse might take a perfect set of conditions to reproduce. Maybe I found the 1 in a million point where all three systems went "duh, huh?" for a second.
 
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Sounds plausible. I mean I always drive with my TC off. I could shut it off from the Predator but, I prefer to make that call in cockpit as I do drive in rain at times.

Sounds like TC issue with the cutouts and hesitation. A GT with a tune should definitely NOT be doing that.
 

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Well, I can tell you that mine will do it everytime I drive to or from ABQ to LA. It's about a 900 mile trip, and it will hesitate after the car has been on cruise for a while. Could be something with the fuel trim, timing curves,etc after the car has settled into a "Cruise" mode. Never does it when I'm not using cruise, but I'm in and out of the throttle all the time with it. It does not do it all the time, but it's always the same when it happens. Hard accel after cruising, usually includes a downshift to a lower gear, and there is a split second hang, (like someone cut the throttle), but the boost is still there. Almost like someone just killed the spark at WOT for a second, then it resumes just fine. Maybe I'll try to catch it on a datalog. FYI, this did this when the car was bone stock, before any mods at all!!
 

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Mine has done this since I got about 1000 miles. I can reproduce it almost everytime I go on a long trip, kick into 3rd to pass and give it the gas. It stutters 2-3 times if I don't let off the gas, then goes. I always turn off TC, so that doesn't help. I've found what does help is to turn the A/C compressor off before passing. Even doing that, I got a very small stutter one time after I cut it off, but nothing as bad as the 2-3 stutter with the A/C on. I have a custom tune from DTP Racing, but it still does the stutter.
 

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I also have the hesitation problem on my 05 GT. I can duplicate it, but only after driving for a while at highway speeds. Once, it caused a dangerous situation while trying to merge with traffic-- when I really needed to go, not sputter. My dealer couldn't duplicate the problem, but I hope Ford is aware of it; this could possibly cause an accident.
 

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It seems to be related to the amount of time that you are at cruise. I have to be cruising for least 20 minutes with little to no throttle input changes before it will hesitate. I swear the throttle body is snapping closed for a split second. Now that being said, folks that never drive on highways for extended periods are more than likely not going to experience this malfunction. It is a wide spread problem, it's just that some owners don't keep their right foot still enough to cause the malfunction.The other day after cruising on the interstate for 40 minutes, I put the car in neutral and blipped the throttle just before I got off my exit. The car never stumbled at all after stopping at the light. Now I have driven this same highway before, gotten off the same exit, and the car always stumbled after stopping at the light. It's almost as if the computer gets confused.
 

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05AV6 said:
It's almost as if the computer gets confused.
A confused computer??? How could that be?? :rolleyes: Maybe Bill G is under the hood!!! :sterb:
 

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Im not nuts! thank you all for posting , i thought i was the only one with this problem...I get that hesitation at a stop after hwy cruse and it almost got me into a big accendent at a stop light. Im taking all of these posts to my ford dealer so they know im not nuts. I hope we can get a fix before someone gets hurts..thanks guys and by the way, I love my Mustang!!!!!
 
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