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Q: Tbi problems

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My son recently hooked the battery up backwards. Luckily, i yanked it out of the vehicle before the fire would've started. Now... the tbi isn't receiving any fuel. New pump, sending unit, relay, lines, and ecm. Have spark, pressure at the throttle body, and fuses are good. Injectors refuse to spray. Why? I NEED this truck to work. NOW.
My car has a manual transmission.

The fuel injector is a simple part. You can test the injector by giving it power and ground. If there is fuel pressure, it will spray for as long as you hold the power on. You can also check the electrical resistance. It should be around 1.5 ohms.

The injector receives power through the ECM fuse. It should have power with the key in the run and start position. The ground comes from the ECM. You will need a noid light to test the ground pulse from the ECM.

There are several fusible links to check too. The smaller wires connected to the starter battery pole are powered at the starter. That’s where the fusible links are. Pull on them to test. If they are flexible, they are blown.

How did you check your fuses? They should have been checked with a test light to verify they are powered.

If you need more help, consider YourMechanic, as a certified technician can help you with your fuel injectors and pinpoint any other problems your car is having. We come to you.

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