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Q: I can't get the car to turn over

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It like there no when you try to turn it over theres nothing i have all the dash lites working and iv change the starter put a different computer on it and I don't have fuel pressure either
My car has an automatic transmission.

A: To start, computers, aka PCM (powertrain co...

To start, computers, aka PCM (powertrain control modules) rarely fail. They are complex units that require many different inputs to initiate the desired response. Having replaced your PCM already, you may have already traded in your old PCM as a core. If you happen to still have it, I would plug it back in and continue by doing some testing at the starter relay. From the relay you can check to see if it is the PCM that isn’t commanding the relay to supply power to the starter ored if there is something else wrong.

It is possible the relay is the source of the problem. You will need a wiring diagram and then you can use a jumper wire to supply power to the starter solenoid from the relay connector. If the starter turns over, you have confirmed that this part of the starter system is good.

Having replaced the PCM, this is likely the cause of the lack of fuel pressure. As far as why it won’t crank, you have complicated the issue by replacing the PCM. The new PCM needs to be programmed using a professional scan tool. If you have already done this, then you can begin diagnosing the no crank, assuming the PCM has been successfully programmed.

If you should still need help with this diagnosis, I recommend the following inspection to help you out. A certified professional from YourMechanic can come to your car’s location to diagnose the starting issue and assist with repairs.

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