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Q: New motor, ran good one week but now will not start. Changed multiple sensors. It will try and start with the throttle body wide open

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Has fire, fuel, and compression, cam and crank sensors replaced. If throttle body is held open it will almost crank then die. Confirmed 50 psi from pump and all injectors are spraying fuel. Please offer any advice? 2002 Dodge Ram 1500, 3.7 liter v6

My car has 170000 miles.
My car has an automatic transmission.

A: Hi there. The first thing you could do is c...

Hi there. The first thing you could do is check all fuses. On some vehicles, for example, the fuse to the power door lock provides power to a module that initiates a "start" signal to the PCM. Although you do report that it ran fine for a week, you may want to consider the age of the gas in the tank. If it is older than two months, drain the tank and use fresh fuel. Old fuel will not start an engine at times.

Opening the throttle plate, and thus introducing more air and it then getting "closer" to starting, insinuates a possible air-fuel ratio problem, potentially too much fuel. Are the plugs wet? Does the Check Engine Light come on when the key is in the "On" position (thus signifying PCM is on line and in diagnostic mode)? If so, what are the trouble codes set?

It is possible the car’s Engine Immobilizer (security system) is locked out. Try disconnecting negative terminal from battery for 10 minutes and re-connecting for a reset. If your car is equipped with a transponder key, try a different, known working key. If none of this works or you need further help, I recommend having a qualified professional, like one from YourMechanic, diagnose and repair the starting issue.

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