Contour Enthusiasts Group Archives Forums General Troubleshooting V6 Throttle Hang

Hi, I have visited this forum occasionally whilst trying to resolve my throttle hang / idle flare problem 2.5 V6 Mondeo, and wonder if I could ask you for some information.
I just can't accept that the car was designed to do this from day one, Ford have TSB's out on other models to resolve this problem when it happens.
Has anyone noticed that the problem goes when the vehicle speed sensor is disconnected.
Another question, has anyone replaced the ECU in order to try to resolve this.
Thanks for your time
James

Hi! If you would've checked out mod's and how to's on the main page you would've found this.

Throttle hang fix (TH fix)

Crikey that was quick, thanks, I have tried this mod with the copper plug but this cures the symptom, I am still not convinced that the car should do this.
James

Ford has had a few re-flash updates available for the ECU, but none cure the problem entirely. Apparently even Ford can't figure it out. Many/most CEGers have been running the plug fix for hundreds of thousands of miles with no issues, so I would just install it and forget it.

Also have a look at this thread.

http://www.contour.org/ubbthreads/showflat.php?Cat=&Board=trouble&Number=602966&page=0&view=collapsed&sb=5&o=7&fpart=1

Thanks guys.
I have found two ways to prevent this problem.
1. Disconnect the vehicle speed sensor and the car drives fine, only problem is no speedo, ABS, TCS or air bags, not good, but this proves the problem is electronic.
2. Remove the TPS from the throttle housing but leave the wiring connected, again no throttle hang, only problem, revs bomb down when your foot touches the clutch pedal, but again this proves the problem is electronic.
I understand the TPS controls injection shut off on overrun and I know that my injectors are not shutting off when they should. I've changed many parts, and carried out many tests, all the obvious ones but now my suspicion is focusing on the ECU, I have been advised that they are prone to 'dry' soldered joints inside, possibly the chip is not 'seeing' the TPS signal fast enough because of this.
I intend to send my ECU for testing (and repair if required) in the next two weeks or so and will keep you posted.
James

I am sorry to bother with such a simple question, but this is all new to me. I have searched through many posts and found many descriptions of what causes throttle hang (an air-flow issue, caused by a lack of pressure?), but my question is, what exactly is throttle hang, and what are the symptoms. Lastly, is this an issue only for MTX vehicles? Any information would be appreciated. Thank you.

P.S. - I have read and mostly understood the FAQ on this, but I simply do not have the knowledge of the jargon used on working on cars. Thanks.

A description of throttle hang would be that the RPM stays up after releasing the throttle for a few moments. This is done for emissions purposes. Keeping the idle high for a little bit helps burn up excess fuel to keep the tailpipe reading cleaner while slowing down.

It is generally felt that the Contour engineers somewhat overdid the throttle hang, and it can be more pronounced than intended if the computer has mislearned, if the idle air control valve is sticky and slow to respond and if there are other electronic malfunctions that provide the wrong signal to the idle air control valve.

Throttle hang is not a new concept. Even in the days of carburetors mechanism were used to slow down the throttle return to idle. The most common of which was a dashpot that could be adjusted to alter the throttle closing. Originally it had more to do with preventing engine stalling when slowing down but later was also used to cut emissions.