XJ20
It's no big deal
- Location
- Ten Feet from Hell
My 91 instantly quit running on the way home from work about a month ago. There’s no spark and no gas to the cylinders. There’s plenty of gas in the fuel rail and holds pressure for weeks. There’s no spark at the plug and the coil tests good. I have voltage everywhere I think voltage needs to be. There’s not a trace of fuel smell or wetness in the cylinders.
I’ve tried three cps and tried another known good ecu with no luck. Two new cps as well as the old one fail the voltage break test even though there is 5+ volts going in and coming out, it just won’t make and break the voltage as the engine cranks over like it is suppose to. I don’t know why that is and what would that have to do with no injector pulse anyway.
So I have repeatedly started back at the beginning with the testing. I must be overlooking something that both control the cps and the injectors.
The only points of voltage that I haven’t been able to check are all the pins for the ecu. I can’t find any info on which pins should have what voltages in and out. There is full voltage out from the ignition fuse and all sensors have proper voltage at their connectors.
I want to try some different tests and thinking. I have to assume that the problem is not the cps or the ecu even though all three cps fails to break voltage.
Besides the cps and the ecu what would cause no spark? Wiring and grounds just don’t seem to be it.
Does anyone know why a cps won’t make and break the output voltage during cranking when it has proper voltage going in and passes the ohms tests, etc?
Does anyone know what may control both the cps and the injectors that would have gone out suddenly?
Does anyone know which pins are supposed to have what voltage on the ecu on a 91?
I’ve tried three cps and tried another known good ecu with no luck. Two new cps as well as the old one fail the voltage break test even though there is 5+ volts going in and coming out, it just won’t make and break the voltage as the engine cranks over like it is suppose to. I don’t know why that is and what would that have to do with no injector pulse anyway.
So I have repeatedly started back at the beginning with the testing. I must be overlooking something that both control the cps and the injectors.
The only points of voltage that I haven’t been able to check are all the pins for the ecu. I can’t find any info on which pins should have what voltages in and out. There is full voltage out from the ignition fuse and all sensors have proper voltage at their connectors.
I want to try some different tests and thinking. I have to assume that the problem is not the cps or the ecu even though all three cps fails to break voltage.
Besides the cps and the ecu what would cause no spark? Wiring and grounds just don’t seem to be it.
Does anyone know why a cps won’t make and break the output voltage during cranking when it has proper voltage going in and passes the ohms tests, etc?
Does anyone know what may control both the cps and the injectors that would have gone out suddenly?
Does anyone know which pins are supposed to have what voltage on the ecu on a 91?
