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Q: start and go

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During the winter, we lost the key to our truck. Brought it to the dealer and had a key made. Ever since then, it has a start and go problem. Brought it back to the dealer snd they put in a new starter. Worked ok for a few days, but went right back to the problem. Took it backseveral times, they couldn't find anything. Still doing it. Perplexed!! Whatdo think is going on?

My car has 81729 miles.
My car has an automatic transmission.

A: Your truck is equipped with an immobilizer ...

Your truck is equipped with an immobilizer that may be having a problem intermittently reading the key. The immobilizer is a security feature that has to recognize the chip built into you key in order for the vehicle to start. It’s a great anti theft feature, but unfortunately adds a whole new element into problems with cars not starting. If the problem started only once the new key was used, then it’s likely a problem with the new key, though the entire system should be checked for proper operation. Unfortunately immobilizer part replacements usually can only be done at the dealership, but for a second opinion, you can have the system diagnosed by an independent technician, such as one form YourMechanic.

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