Q: No injector pulse but does spark.

asked by on January 02, 2017

After replacing the transmission on my truck I found out it was cranking and would not start. I put a test light and no pulse from either injectors. I also checked and there was spark. So far I know my ecm is good. Im thinking it is my crank sensor or my pick up coil but im not sure if my truck would spark if those two things were bad. Please, I need help. Thank you.

My car has 100000 miles.
My car has an automatic transmission.

Hello There, You are correct in that if the crankshaft position sensor or the pickup coil were bad there would likely not be any spark to the plugs. In relation to your no injector pulse problem, check the wiring harness from the distributor to the ECM. If that harness has become disconnected somehow, the ECM will not have a pulse reference from the distributor in order to fire the injectors. Also, make sure that you actually have power to the injectors, as there are 2 fuses that supply them. Make sure these are not blown. If there are connectivity problems, sometimes these will draw too much current and cause them to blow. If you need additional assistance, I would recommend having a professional from YourMechanic come to your location to diagnose and inspect your injection system.

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