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Q: Can't Start Engine after rebuild

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We had to replace the head gasket due to a compression leak in #5 to the cooling system. (Before this happened the car ran great with no problems). We disconnected the battery, stripped the engine down, had the head re-ground at an engine shop. Replaced the head bolts, gaskets, plugs etc. and put everything back together.
Then it wouldn't start. 1) We checked the fuel pump system and ECM relay drive. The fuel pumps runs during cranking. 2) We checked the fuel injectors with a test light. When cranking, they flashed 2 times in the first 2 seconds. 3) We tested the pick up sensor with a 1 volt meter. Manually turned the engine, the meter moved indicating a pulse. 4) Using an old time timing light tested the coil / spark output. While cranking, it flashed a couple of times in the first 2 seconds. 5) We check the MAP sensor and other sensors 5 / 12 volt power sources and ground. Our problem is when we crank the engine, the ECM will only fire for the first 2 seconds and then nothing

My car has 120000 miles.
My car has an automatic transmission.

Hi - congrats on being very thorough with your testing! If you spritz some starter fluid into the throttle body, will this start it for a second or two? That would confirm the total of your testing - that you have spark and fuel (temporarily) - resulting in combustion. If spraying gas into the throttle body allows the engine to run longer, you have isolated the problem to fuel supply. Coolant sensor failures (the sensor for engine management, not the gauge) are known for causing ECM problems with this engine, and it’s possible the ECM is bad period. I would recommend having a Car Is Not Starting Inspection completed by a mobile, professional mechanic, such as one from YourMechanic, to diagnose this problem if you are requiring of further assistance.

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