nu2ford

I had a bad throttle position sensor the other day on my 05 (96K miles). My car was built in Feb of 05. The throttle position sensor has progressed (improved?) two levels sincemy model came off the line. My dealership told me that to fix it was going to require replacement of the Electronic Throttle Body (ETB). This was not covered under the extended powertrain warranty. That repair would have cost me $340+ for the part and another $300 for the installation $640 for the totalrepair.
I suspected the throttle position sensor was the cause of the failure ($80). I went to the parts window and ordered one. It takes all of 10min in your driveway with only a torx bit (forgot the size) to R&R the part. The failure mode has not repeated since.
By the way, the failure mode is:
The 4.6L 3V engine does not return to idle after low engine revs. Basically when driving down the street and coming upon a stop light the engine coughs, spits and eventually stalls. It will start back up but may not idle. This failure will also potentially cause the Engine Control Unit (ECU) to go into limp home mode and set codes for the TPS, Throttle plate motor and MAF sensors.
Be sureto not confuse this symptom witha similar failure caused by the fuel pump (TSB available).The fuel pumpfailuremost likely will not setcodes. The fuel pumpfailure most often occursafter long highway drivesthen transitioning to idlewhen exiting the freeway. The engine will stall due to air pockets getting into the fuel line caused bya fuel pressure loss.

muswang

I am having a problem kind of similar to this.
I own a 06 GT. About two months ago, my car started self revving (for lack of better term?) almost everytime I'm coming a stop light. I'd be in neutral, my foot not even near the gas pedal and it would just rev... 1000rpm, 1500 rpm until i came to a complete stop, my foot on the brake.
I took it into the dealership and they reported nothing was out of the ordinary. However, they did call Ford (company??) and stated that some of the V6's were having that problem, and some of the V8's. Supposedly, Ford is looking into this issue now.
That is what I was told.

Anybody else with this issue?

ohfiveride

yep same problem on my 05 gt.....i took a voltmeter to the tps and it was way off......i ordered a new one (and improved as well) from ford motorcraft (newfordparts.com).....word to the wise tho..when taking out the old torx bits use a srcew gun of some type like the instructions tell you bc i didnt and the heads broke off and i had to get a machine shop to drill them out...THIS IS A COMMON PROBLEM APARENTLY.......i noticed that the old tps had no spring loaded tension so im guessing thats part of the problem...the new tps i got had a metal lining inside where the throttle blade screw goes into so it wont strip and it had some tension on it.....

nu2ford

My experience with TPS is that an incorrect voltage on the TPS is what will cause the throttle position to be misinterperupted however that shouldn't cause it to go to high rev until the vehicle stops. If there is a misreading it tends to stay there until something causes the TPS to move thereby changing the voltage measurement and allowing the proper position to be read.
In the case where an engine is revving higher during a stop, I'd be more concerned that the gas pedal is being pressed at the same time as the brake with the right foot. If this happens again, be sure to swap feet and brake with the left to see if it goes away. Of coarse if you wish to swap out the TPS it may not be a bad thing as your '06 should still have an older OEM part than what is currently available as a replacement. The one I got the other day had a prefix for an '09MY. There are many reasons to change part numbers like that. Ford changed suppliers or they improved the part. Possibly the material or dimensionchanged (plastic/metal).
Good luck with your fix. Please be sure and investigate that the the throttle plates are closing all the way. Cleaning them with an approved cleaner may fix your problem. There is also the off chance that the throttle plate motor may be bad or hanging up. If there were no codes found when you took it to the dealer, I'd rule the motor and a sticking plate out.

ohfiveride

nu2ford.......its not the high revs, its the low revs while stopping that causes the stall outs and bad idle.....it sounds like you havent had this problem yet....i say yet bc its very common and ford knows somwthing about it.....yes my replacement tps was different..looked improved and better made than the stock.....the bad tps units usually arent throwing codes and thats why its frustrating..i had no idea until i cleaned my air filter, changed my fuel filter, cleaned the throttle body that it could be something else....but it was....

JDBullitt

I had the same problem nu2ford, luckily,mine was still under warranty.