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Discussion Starter #1
Hey guys, having a problem with the car not starting. I swapped vehicles with my buddy for the weekend and he said he came home for an hour and then went to jump in the car again but it wouldn't start. Battery is good, he even put the battery on charge over night but still nothing. I checked the codes on my Peake and got the following

51- MFL interface signal
D0- misfire during warm up cyl 4
D1- misfire during warm up cyl 5
D3- misfire during warm up cyl 7
D5- misfire during warm up, multiple cylinders.

When turning the key to pos 3 there's no clicking from the passenger floor area (starter relay?). I'm not sure the 51 code is relevant to the car not starting but it's causing some very odd issues with the steering wheel and radio. In ignition position 1, the dash lights and radio continuously turn on and off. In position 2, the steering wheel moves up and down on it's own, the headlights keep auto adjusting and flicking on and off, and the airbag light flashes every few seconds. According to my buddy it wasn't doing any of that before the car wouldn't start. Then again if he always just put the key in and started it right up (pos 3), he may have bypassed and not noticed any of the issues in pos 1and 2.

Thoughts? It would be nice to not have to tow it to the shop :/
 

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Your car is newer so the starter relay is in the glovebox. I would say check the starter but this is almost definitely your ignition switch if we are thinking electrical problem and keep it simple. I would just replace it without much delay only because they are known to fail. If you replace it and the problem still happens then it will be a pretty serious electrical diagnostic you will have to do.
 

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Code 51 means that your horn and steering wheel buttons are not working properly and it's not related to not starting. To fix that you will need a new clock spring but since your steering wheel is moving up and down that's probably faulty ignition switch. Misfire during warm-up codes are all related to vacuum leaks. Get the car smoke tested once you get it to start and let us know.
 

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There are most likely other issues, but I would start with the quick and easy...check the battery connections. The beast insists on clean, well greased battery-to-cable connections.
 

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Discussion Starter #5
Sailor nails it again. New ignition switch fixed it! Getting that one T30 torx out was a royal pain. Had to go buy a knuckle attachment for my ratchet. The switch must have been on it's way out for a while because the response to turning the key now is somehow more immediate and less vague. I would also occasionally get some false starts before. Even though my car is an 03 it looks like this isn't the first time it's been replaced. The red paint on the screws was already scratched off and the torx teeth were definitely used. Busted the clips on the brushed metal trim piece to the left of the wheel column. Hoping some super glue fixes it.
 

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Discussion Starter #6
Sailor nailed it. Ignition switch. My car is an 03 but judging by the scratched off red paint on the retraining screws and the well used torx teeth, this isn't the first time this part has been replaced.
 

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Just swapped mine out too, with totally different symptoms. . . these ignition switches are quite interesting in how they present!
 
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