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Car died and wouldn’t go over 1000Rpm or 5mph

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#41
Where would I start with the brake switch code? What sensor would trigger that?
Seems like you've sent it to the proper place where they can troubleshoot the sensors with the proper fsm tree.

there are sensors to monitor pedal position, throttle pedal position, throttle plate position etc... all have to be working in harmony otherwise you get a bunch of codes. All you need to usually focus on are the main ones, all of the secondary codes are a result of the car operating in limp mode so yes, if timing is pulled way down and throttle is artificially closed then the ecu sees those as new issues as well etc... so once they fix the first one things should become more obvious.
 


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zanethan

zanethan

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Thread Starter #42
Seems like you've sent it to the proper place where they can troubleshoot the sensors with the proper fsm tree.

there are sensors to monitor pedal position, throttle pedal position, throttle plate position etc... all have to be working in harmony otherwise you get a bunch of codes. All you need to usually focus on are the main ones, all of the secondary codes are a result of the car operating in limp mode so yes, if timing is pulled way down and throttle is artificially closed then the ecu sees those as new issues as well etc... so once they fix the first one things should become more obvious.
Well the dealer is stumped too. They couldn’t get it to misbehave and ultimately reset all the computers and said bring it back if it does it again.

So l guess I officially have a gremlin which has me second guessing keeping the car now.
 


TyphoonFiST

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#43
Well the dealer is stumped too. They couldn’t get it to misbehave and ultimately reset all the computers and said bring it back if it does it again.

So l guess I officially have a gremlin which has me second guessing keeping the car now.
So did they re-flash it?

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zanethan

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Thread Starter #44
So did they re-flash it?

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I had already uninstalled my AP to eliminate that as a cause (although I never actually thought it was) but yes. Per the service writer they reset and updated all ‘modules’. I haven’t picked it up yet to see what was written on the ticket. It was clear that they suspect my dashboard camera and pillar gauges most so I’m not sure how thorough of a job they actually did.
 


TyphoonFiST

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I had already uninstalled my AP to eliminate that as a cause (although I never actually thought it was) but yes. Per the service writer they reset and updated all ‘modules’. I haven’t picked it up yet to see what was written on the ticket. It was clear that they suspect my dashboard camera and pillar gauges most so I’m not sure how thorough of a job they actually did.
They flashed it I'll put money on it

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zanethan

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Thread Starter #46
They flashed it I'll put money on it

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Probably. The notes said reset and installed update on PCM so I guess I’ll see if it does it again. Hopefully it doesn’t do it while on the interstate.
 


D1JL

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#47
As I said before, intermittent problems are toe worst to diagnose.
Let's hope your problem is solved.
 


Intuit

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#48
To have all that go out at once is unlikely. Some wire harness was disturbed when you were "modding". Need to retrace your steps. Listing out the codes will likely point to a particular harness that all these various sensors have in common. Not a Ford, dealer, or moderator problem, but a user one.
 


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zanethan

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Thread Starter #49
I normally would agree that it’s a disturbed wire during working on the car but in this case I haven’t worked on my car in months. Also, the electrical mods I have (pillar mounted gauges, dash camera, and seat airbag bypass (just a resistor due to aftermarket seats)) have been on there for thousands of miles without incident. I’m not ruling anything out but I’m doubtful in this instance. I plan to see if the PCM update resolves it before touching anything else. If it does it again I plan to take it back to stock and then the dealer for further diagnosis. If they can’t find it again, it may be time to move on. I love this little car but I’m not going to put fun over my families safety.

I appreciate everyone’s efforts thus far but it looks like this ones just too complex to figure out via the forums. I’ll update if this gets resolved.
 


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zanethan

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Thread Starter #50
Just wanted to update everyone on this. The dealer reset and updated the PCM and I believe that did fix it as it didn’t stall after the update and I drove it around as much as possible afterward.

I won’t be able to fully verify as we traded the FiST in on Tuesday. This issue lead us to consider trading in the FiST and after crunching some numbers it just didn’t make sense to keep the FiST. We had 4 cars and the FiST just never got driven. We also don’t have a garage so it just sat exposed to the elements and was slowly wasting away.

As I mentioned in my other thread, some goodies will be going up for sale once I get pictures but if you think you’ll be interested PM me.
 


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