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Q: wont start

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replaced the fuel pump and have pressure at the injector rail. bypassed rear interrupt switch for fuel pump still wont start. checked relay for fuel pump. can you please help

My car has 202000 miles.
My car has an automatic transmission.

If the original problem that caused you to replace the fuel pump was diagnosed as "fuel starvation", check for proper operation of the fuel injectors themselves. If the injectors are not functioning, even if there is fuel supply there will be no fuel delivery. Also, if the engine coolant temperature sensor has failed, the PCM might not be outputting the necessary enrich signal to the injectors at cold start. If you suspect fuel starvation, you can try starter fluid. Obviously, if the engine runs momentarily with starter fluid, the problem is likely in the fuel system. Broadly, if the starter motor is turning the engine over rapidly, at sufficient RPM, but the engine does not catch and run, that means that there is an ignition, fuel, air induction, or mechanical fault in the engine that will have to be repaired. On any engine, if compression is within factory specifications, and there is fuel being delivered by the injectors (not just "to" the injectors) and the ignition system is working, that means that the air fuel ratio of the mixture delivered to the cylinders is so far off the mixture won’t ignite. Such could be due to an air induction fault like a stuck idle air control valve or, as noted, could be due to a failed temperature sensor that must be working properly to signal the PCM to enrich the mixture on cold start. Regardless of the underlying cause, if you request a no start diagnostic the responding certified mechanic will get the problem diagnosed and repaired for you. Please let us know if you have further concerns or questions as we are always here to help you.

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