Have a 2005 ls v6 with about 56000 miles. Recently its been going into what I guess is fail safe mode (the car drops down to idle while driving and won't accelerate at all). Pulling over and shutting off the car and turning it back on gets things normal again until the next occurrence. I noticed today a constant check engine light on so I had the codes pulled at the local auto store and got P2104 (TAC system forced idle) and P2112 (TAC system stuck closed). I tried a little throttle body cleaner and disconnecting the battery for a while and that didn't work as I experienced the problem again and also noticed the little wrench warning light came on (Electronic Throttle Control). I'm just looking for some advice and or confirmation on what it might be as from what I read it's either the throttle body or the coils. I haven't had any idle or misfire or stall problems with it. I can do the work myself but just don't want to waste time buy and putting on unnecessary parts. Also does the extended warranty for the coil issue cover 6 cylinder ls's also? Thank you.
limp mode question
- Thread starter abe2571
- Start date
Rifleman@LaymansPC.com
Well-Known LVC Member
I had a similar issue with my '04 V6 not long ago. Those are both codes I was getting intermittantly (along with several other throttle codes) for a few months before my battle with my P0108 code in another thread (http://www.lincolnvscadillac.com/showthread.php?t=52717). That ended up being a bad EGR module.
Before changing the EGR module, I had continued driving the car and recording all codes that came up. One was an odd code that led me to a TSB stating the Throttle Position Senor should be changed and the PCM flashed. I took it to the dealership, it cost me just under $200. The TPS housing was warped and deformed from heat or high voltage or whatever. I had drove mine for a month with the random "fail safe mode" issue before getting the oddball code that pointed me in the right direction.
TSB info here >> http://bradbarnett.net/mustangs/galaxie/tsb/tsb05_14_04wrench.pdf
Bad part in my situation was that even after having the TPS changed and PCM reprogrammed, I was still getting the fail safe mode intermittantly. That's when the digging went deeper and also found the EGR module.
I would say get the instructions on the TPS removal and installation and pull the TPS off and visually inspect it for the same deformed housing. If you have the deformation of the housing, take it to the dealership with the above TSB article and also have them fully inspect the EGR module for proper operation and ask them to test the 5V circuit at the ERG module. If they say it needs changed or the voltage is a little high (+/- 0.2V was the acceptable range of variance from 5.0V), I'd recommend purchasing the ERG module from rockauto.com (price from them for the stock Motorcraft part was about $85 as compared to the local dealer price of $150.84). Two 10mm bolts and a hefty crescent wrench and you can do it yourself in 5 minutes. It mounts right at the front of the upper intake on the passenger side. The TPS is right on the throttlebody and held by a couple screws.
Our cars are virtually identical other than the model year. Mileage fits the scenario too. Sounds OH so familiar to me,, hope you get it whipped.
Good luck. Let us know where it goes.
Before changing the EGR module, I had continued driving the car and recording all codes that came up. One was an odd code that led me to a TSB stating the Throttle Position Senor should be changed and the PCM flashed. I took it to the dealership, it cost me just under $200. The TPS housing was warped and deformed from heat or high voltage or whatever. I had drove mine for a month with the random "fail safe mode" issue before getting the oddball code that pointed me in the right direction.
TSB info here >> http://bradbarnett.net/mustangs/galaxie/tsb/tsb05_14_04wrench.pdf
Bad part in my situation was that even after having the TPS changed and PCM reprogrammed, I was still getting the fail safe mode intermittantly. That's when the digging went deeper and also found the EGR module.
I would say get the instructions on the TPS removal and installation and pull the TPS off and visually inspect it for the same deformed housing. If you have the deformation of the housing, take it to the dealership with the above TSB article and also have them fully inspect the EGR module for proper operation and ask them to test the 5V circuit at the ERG module. If they say it needs changed or the voltage is a little high (+/- 0.2V was the acceptable range of variance from 5.0V), I'd recommend purchasing the ERG module from rockauto.com (price from them for the stock Motorcraft part was about $85 as compared to the local dealer price of $150.84). Two 10mm bolts and a hefty crescent wrench and you can do it yourself in 5 minutes. It mounts right at the front of the upper intake on the passenger side. The TPS is right on the throttlebody and held by a couple screws.
Our cars are virtually identical other than the model year. Mileage fits the scenario too. Sounds OH so familiar to me,, hope you get it whipped.
Good luck. Let us know where it goes.
joegr
Dedicated LVC Member
This has happened once to my wife in our 04 LS (V8). There were no warning lights or messages. I scanned for codes right after it happened, and there were none (except for a DCCV shorted warning which cleared). I also checked and the misfire count on all cylinders was zero. That was about a month ago and hasn't repeated.