silva4124

Howdy,

After driving my 5-speed for a bit, whenever I put it into neutral and take my foot off the clutch (say, when approaching a red light), the engine will rev up to somewhere between 1500 and 3000 rpm. It'll hang there for a few seconds, drop back down to normal (under 1000 rpm), then pop right back up. The cycle will repeat itself a few times, usually at least three. Sometimes it helps to push in the clutch, but not 100% of the time. If I push down on the accelerator while it's revved up, the rpms just climb higher.

One night I stalled it twice because when I gave it gas, the accelerator didn't respond and therefore I pulled the clutch out and stalled it. I figure something's wrong with the accelerator somewhere along the line, but I honestly have no idea.

Any ideas? Your help is greatly appreciated. I just bought it used.

Thanks and Gig 'Em

lundefinedl

Maybe the drive by wire has gone funky?

I got mine used at 30k miles and the first week I had it the throttle body went completely haywire and the car went into limp home mode.

BWfVA

yea i am just guessing here but I would be willing to bet that it has something to do with the drive by wire system in that TB

157dB

Sounds like the previous owner did the throttle pedal
'bend the little metal springs' modification that was going
around here about a year ago and it finally took its toll on
the potentiometers inside the throttle pedal control.
I would go to the Zone and have them check for any DTCs that might
have been thrown in order to get to the root of the problem.

silva4124

Dang, so it's possible that it's something the previous owner did? Someone else suggested that there could be a vacuum leak or the EGR valve could be malfunctioning....

28HopUp

What you've described is a somewhat common problem with the 4.0L/5spd S197's. My old coupe did that and I found it to be very annoying. I never was able to fix it. The revs WOULD drop off when I'd press in the clutch all the way though...

EVILHORSE

I have the same issue but only noticed it after installing
The bamachips tune .by the way I also have a 5 speed

silva4124

Yeah, the previous owner put on the California Special package after he bought it, so there's really no telling what he did to the inside of the hood. I got if from a used car dealer, so they have no idea.

It's at the dealership right now, so I'll update on what they say.

gppford85

my wifes 05-V6 does the same thing. she stoped at a local mustang show last summer and talked to some guys who said that it is a programming issue with the fly by wire. a guy had suggested to take it to good tuning shop and they might be able to reprogram it but i am still hesitant to do that. i have been looking for fixes to that issue but with hers when you come to a stop i just press the gas peddle in and it comes down to normal.

kevinmalec

I have the same issue with my 2005 4.0 and it is also a manual. I installed an Airaid CAI and it happens less frequent now. When the idle starts increasing, I usually hit the gas pedal and the idle goes back down. If any body finds out a resolution, let everyone know! I am curious myself. :-)