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Q: My car will crank but won't start. It gets fuel and I just replaced the coil pack - what could be the problem?

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I thought it wasnt getting fuel so i replaced the fuel injecter but it wasnt the problem so i replaced the coil pack but wasnt the problem what could it be?

My car has 215000 miles.
My car has an automatic transmission.

A: With a crank no start condition, you need t...

With a crank no start condition, you need to first determine what your motor is missing. Spark, fuel pressure, injector pulse or cam timing. This is best done with a fuel pressure gauge, a noid light to check for injector pulse, a spark tester to check for spark and a compression gauge to check for proper camshaft timing. I connect everything except the compression gauge first. If I find something missing, I follow that diagnostic path. If everything is present and of course the motor won’t start, I begin checking compression.

If camshaft timing is off, compression will be way off in more than a few cylinders. Lets hope it is not camshaft timing on your vehicle because this is a major problem on your vehicle that may cost more money to fix than the value of the car.

If you are missing spark and injector pulse, suspect a bad crank sensor. The best way to observe the crank sensor is working is with a scan tool. If you are missing only injector pulse, test for power at the injectors with the key on. The PCM grounds the injectors to turn them on. If this isn’t happening and you have spark, suspect the PCM. But keep in mind, PCM’s are not in the habit of failing, so suspect there is something else causing the PCM not to fire the injectors. Security system, etc.

If you are missing only spark, this has to do with the ignition system only. If you don’t have fuel pressure, begin testing the fuel pump at the fuel pump relay. This means remove the fuel pump relay and supply power to the fuel pump to see if it runs. This will require a wiring diagram and some knowledge of these systems.

If all this is too daunting, I recommend a car is not starting inspection.

Good luck!

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