Car has no spark or injector pulse(new ecm,crank sensor)
Car was parked one night next morning it would not start.
I replaced crank sensor and computer . I still have no trigger to the coils for spark and no injector pulse. I have fuel psi, and i have no open on the wires from coil to computer and from crank and cam sensor I have signal
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Have you checked to make sure the security system isn't preventing it from starting?
If not, the cam and crank sensor needs to correlate in order to have injector pulse and spark, so I would start by probing the cam sensor to check for AC current while cranking if there is current ohm the wires to the ecm, if the ohm reading is less than 1 ohm it sounds like a computer problem
Check for spark at 1 or more plug wires. If no spark, possible crank sensor/computer/fuse/wiring. Check for injector pulse. Remove 1 injector harness and install test light between the two terminals of the harness and crank engine. Test light should flash if computer/wiring ok. Make sure check engine light comes on when key in on position for bulb check. If no light, look for blown ECM fuse/s
No spark no injector pulse your saying you check pulse. With the key in the igition is there a key sign flashing and does the key have a battery for alarm. For the fuel pump to operate it need a crank signal so you got the crank correct but no spark so the crank works. Can you check the ignition for pulse you know how it is shape its curved on one side staight on the other side well the curve side and at that end is the ground after that on is the control from ECM. If you can check pulse there then we can go to the ECM . What I am trying to get at is this your alarm is the only thing beside the ECM that can cause this.
spark comes from a couple places you want to check.
2) crank and cam sensor
if you find also the injectors are not getting an injector pulse than your spark problem is leaning more towards the sensors or the ECM.
Test fuel injector pulse and supply voltage output (test is used for most cars). This test will tell you if the computer system has operating voltage and injector trigger signal. Remove an electrical connector from a fuel injector (it doesn't matter which injector) probe both sides of the connector with a grounded test light (there are only two terminals). Have a helper turn the key to the "on" position without cranking the engine and observe the test light. The test light should illuminate one side of the connector only. Next, switch the test light lead to the positive side of the battery to test the system ground injector trigger, probe the side of the connector that did not light up, have a helper crank the engine over and observe the test light, it should blink on and off. If this test checks ok continue to next step. (Note: if no injector pulse is present try disconnecting the remainder of injectors and re-test, if a fuel injector is shorted it can shut down the injector driver causing no injector pulse. If injector pulse returns plug injectors electrical connectors in one at a time until the pulse fails and replace that injector)
If this test revealed that there was no pulse but system has power the ECM is not generating a fuel injector trigger. If there is no trigger to the fuel injector it will not allow fuel to enter into the engine. Some of the most popular reasons that can cause this condition include a shorted crankshaft angle sensor, shorted camshaft position sensor or shorted ECM/PCM. (When a system trouble code scan is performed it does not always catch a crankshaft angle sensor, camshaft position sensor failure). Tip: try disconnecting all non-essential sensors, example: oxygen sensor, coolant sensor, throttle position sensor, air intake temperature sensor, mass air flow or map sensor and EGR valve pressure differential sensor. Crank the engine over, if the injector pulse returns, one of the sensors is shorted causing the system to not operate. Plug the sensors in one at a time until the injector pulse fails then replace that sensor and reassemble.