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Q: Crank no spark after fixing seized engine due to bearing problem

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I need to know why I'm not getting spark.

My car has 155000 miles.
My car has an automatic transmission.

A: I'm assuming the engine was rebuilt, an...

I'm assuming the engine was rebuilt, and not replaced in this scenario. The first thing that came to mind was the crankshaft sensor. Did the new crankshaft come with a reluctor wheel? They usually need removed from the old crank to install on the new one. If you're not sure, remove the crank sensor and look into the hole. It is on the exhaust side of the engine block, closer to the transmission. Check to see if you have injector pulse if the reluctor wheel is present. You will need a noid light. If there is not a pulse, this would support a crank or cam sensor issue. Check for codes as well.

If you replaced the short block, or installed a used engine, and you are getting an injector pulse. Check for power with the key on at pin 3, white wire at the ignition coil connector. The power originates through the "main" relay and a 30 amp slow blow fuse labeled ECM. The ground pulse to the coils comes directly from the computer.

If you need help with this consider YourMechanic, as a certified technician can help you diagnose your starting issue and help you fix it accordingly.

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