300zx wont start
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Picky picky picky lol
Fuel Pump comes on- No spark at the coil packs . The power transistor tells the coils when to fire. That was a common problem on these cars. Replaced that , and still no spark... Cam shaft Sensor is next in the circuit. Would that cause the same symptoms?
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851 Posts
I put $5 on crank angle sensor bad
EDIT: talked to a Nissan guy here at work and he says they don't normally go bad, but they can. He said more than likely it has come loose. Just tighten it. Supposedly easy to get to to tighten. You are lucky.
EDIT: talked to a Nissan guy here at work and he says they don't normally go bad, but they can. He said more than likely it has come loose. Just tighten it. Supposedly easy to get to to tighten. You are lucky.
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8,551 Posts
Did you check for Ig + 12 volts at each coil? The power transistor (module) fires the coils, most likely from the ground side. If there is no Battery voltage ( 12 v + ) at each coil, you wont have spark.
Also You could check the signal from the PCM with a logic probe to determine that the PCM is sending its pulse to the Ig module (or power transistor)
Also You could check the signal from the PCM with a logic probe to determine that the PCM is sending its pulse to the Ig module (or power transistor)
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I would do abunch of checking before spending money on parts.
I would ch eck for 12 v + supply to coil and injectors. Also check reference voltage to sensors.
It would be helpful to extract trouble codes also. You can use an OBD 1 scanner to do so. There should also be a method to get flash codes out of it, you know , count the engine light flashes when the ECM is put into output mode. I just dont remember offhand what to do to the system to get the ECM to test output the codes.But I would certainly do it.
I would ch eck for 12 v + supply to coil and injectors. Also check reference voltage to sensors.
It would be helpful to extract trouble codes also. You can use an OBD 1 scanner to do so. There should also be a method to get flash codes out of it, you know , count the engine light flashes when the ECM is put into output mode. I just dont remember offhand what to do to the system to get the ECM to test output the codes.But I would certainly do it.
Okay, so far: All the fuses have been checked, and all the relays that could be found.. We did find a relay for the fuel pump, believe that it was bad, so we changed it and the fuel injectors are working.. Not getting a fire tough, have tried everything that we know how to do. Got a cam shaft position sensor off a junk 1991 Nissan ZX and that wasn't the problem...
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Going to have to check for trouble codes. You may need to get out an oscilliscope and do some testing also. Outputs for the ignition coils before the Ignition control module will need checked. You should be able to check that with a logic probe. You may be able to check input signals with a DMM. Camshaft and crankshaft signals to be exact. Like I said before, you also need to check for a 5 volt reference signal, also some vehicles use a seperate circuit from the PCM for cam and crank sensors, it may be 5 volts or more. A technical manual would help there.
It could be a defective PCM.
It could be a defective PCM.
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