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Q: Will not start.

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I changed the engine from 97 to 99. Do I have to put the crank sensor and cam sensor from the 97 onto the 99?

My car has 140000 miles.
My car has an automatic transmission.

The sensor will be the same. What you need to make sure of is that the new motor has the tone ring installed on the balancer. The same goes for the camshaft sensor. A missing tone ring is a very common issue with motor swaps. The year of the motor rarely makes a difference. They are still the same motor.

Once you have confirmed there are tone rings for both the camshaft and crank sensors, the next thing to do is to figure out what is missing. Every ICE (internal combustion motor) needs fuel pressure, injector pulse, spark and camshaft timing to run. Figure out what is missing and diagnose the truck accordingly. Something else that is often overlooked, if the replacement motor is a used motor, they will often need some oil squirted into the cylinders to give them enough compression to start. This is normal and does not mean there is a problem with the motor. Don’t squirt so much oil in that the cylinders will hydrolock. A few squirts from an oil can is all that is needed.

Another often missed item, if the replacement motor is used, the injectors can become stuck. Simply use a small hammer to tap on them while attempting to start the motor. This needs to be done with care. Use a stethoscope or small hose to confirm the injectors are working. You are listening for a clicking noise. If you don’t here it, either they are not getting injector pulse or they are sticking from sitting for to long.

I recommend the following inspection to help you figure this out. Car is not starting

Good luck!

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