Got a bizarre issue that I can't diagnose. 2013 Expy El Limited5.4L V8 with 130k miles. Flawless til now. Randomly it throws the wrench symbol and goes into limp mode. Truck runs like it's on 4 cylinders when it's in limp mode. It does this randomly driving or even just sitting in park and idling. Turning off the truck and back on, it clears it and runs perfect. Never throws any codes. Every once in a while it will flash service advancetrac right before going to wrench mode. Anyone experience anything like this? Not sure where to begin since it's not throwing codes. Yesterday while waiting in the school pick-up line, it went to wrench mode, started idling really rough, throttle kept reving itself and about dying. It did throw throttle position sensor codes but I think that was only because of the rough idle. Once I cycled the key, it ran perfect and codes disappeared after a few miles of driving. So confused with it.
Randomly going into limp mode (wrench symbol) and no codes
- Thread starter S281
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99WhiteC5Coupe
Full Access Members
Andrew McDowell
Member
The focus points for me:
1) You are experiencing failure without codes being set "Never throws any codes"
2) The failure occurs during vehicle movement or non movement "at idle" (so that would remove power train as suspect)
3) The condition is reset by turning off the ignition switch and turning it back on (disconnecting switched power)
The tell tell sign is a random, no-code condition which results in Limp Home Mode...
Computers are simple, they are programmed devices which take data (input) and process it (software) into outputs.
In this case the outputs would be
1) Injector sequence and Duration of on/off time
2) Timing of an ignition event (crank, cam input), and in the case of the 5.4 variable cam timing.
3) Firing of the plugs in sequence and at specific times.
Instead of your engine being provided outputs relative to inputs, you are randomly being provided a standard set of fixed outputs and not setting any input failure codes. indicating that your engine management computer is randomly incapable of processing input sensor data into outputs, therefore it reverts to its basic engine functionality.
What this is telling me is that the input signals for the engine management computer are either nill or so far out of spec that the computer cannot accurately process the data. I would therefore suspect (first) the connector terminals at the engine management computer as being faulty (not making adequate continual connection), due to corrosion, the connector being loose, etc. Secondly, I would suspect ignition switch voltage/amperage being provided to the engine management computer (check that circuit as well).
Your failure mode seems to be electrical not mechanical.
1) You are experiencing failure without codes being set "Never throws any codes"
2) The failure occurs during vehicle movement or non movement "at idle" (so that would remove power train as suspect)
3) The condition is reset by turning off the ignition switch and turning it back on (disconnecting switched power)
The tell tell sign is a random, no-code condition which results in Limp Home Mode...
Computers are simple, they are programmed devices which take data (input) and process it (software) into outputs.
In this case the outputs would be
1) Injector sequence and Duration of on/off time
2) Timing of an ignition event (crank, cam input), and in the case of the 5.4 variable cam timing.
3) Firing of the plugs in sequence and at specific times.
Instead of your engine being provided outputs relative to inputs, you are randomly being provided a standard set of fixed outputs and not setting any input failure codes. indicating that your engine management computer is randomly incapable of processing input sensor data into outputs, therefore it reverts to its basic engine functionality.
What this is telling me is that the input signals for the engine management computer are either nill or so far out of spec that the computer cannot accurately process the data. I would therefore suspect (first) the connector terminals at the engine management computer as being faulty (not making adequate continual connection), due to corrosion, the connector being loose, etc. Secondly, I would suspect ignition switch voltage/amperage being provided to the engine management computer (check that circuit as well).
Your failure mode seems to be electrical not mechanical.
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I'am having the same problem with my 2017 XLT, 97K miles. All shut downs happened in operation, while gentle acceleration around 20 to 40 MPH. On one I plugged a portable code checker in, before shutting down the engine.....no codes. Yesterday, I did a full reset on the PCM using FORSCAN. I'm keeping the laptop with FORSCAN stowed under the seat, waiting for the next event.
Got lucky, had FORSCAN in the car when the wrench came up.
PCM P2112:00-A7 Throttle Actuator Control System
OBDII P112-P Throttle actuator control system Stuck closed
This does point towards the throttle body mentioned in a previous post.
PCM P2112:00-A7 Throttle Actuator Control System
OBDII P112-P Throttle actuator control system Stuck closed
This does point towards the throttle body mentioned in a previous post.
I have a 2011 EL XLT with the tow package had this happen once while towing our camper and disengaging tow button and the turning it back on
While going up a hill freaked me out but shutting off engine for a few minutes cleared it all up
While going up a hill freaked me out but shutting off engine for a few minutes cleared it all up
mlogan
Well-Known Member
Exactly what happened prior to my throttle body replacement. Fixed.
