Hello coupe folk - On a drive of approx 1 hr, returning, there was a bit of intermittent subtle misfire followed by some rough running and I barely got back. Now will not start.
Compression between 168 and 178 all cyls, spark present at each plug wire, fuel pressure 2.07 bar, ecu voltages partially checked showing correct temperature sensor resistances, correct ECU and Fuel Injector supply voltages, I think OK throttle switch performance ( tough to gauge w VOM only). NOID light test of fuel injectors showed NO flashing of lights to all injectors !!! Fuel injector circuit resistances tested from ECU : pin 3- 5 was 2.6 and pin 4-6 was 3.6 Pin 3 - 5 is in spec pin 4- 6 may be high dont know what to make of it. I have not yet checked the distributor trigger point system ( for the injectors). Fuel pump seems fine, but seems to run continuously. Fuel flows continuously to the rail when the pump actuates. I cannot figure out how to check the trigger signal for the injectors at the ECU and I do not have an oscilloscope, but I could take apart the distributor and measure cam excursion I guess and use VOM to look for rapidly fluctuating signal at he plug. Would appreciate any suggestions on the approach, I have the excellent jetronic.org web site and have been following those sometimes tough to understand instructions
Car has about 1000 mi since last valve adjustment. I have not done any ignition testing other than looking for spark, which again seem fine and strong. Plugs looked great but I need to test them individually ( used one plug only for testing for spark)
I am wondering how to find the fuel injector system relay ? From diagrams and the shop manual, and various wiring diagrams, I cannot yet figure out if there is a separate relay that may control fuel injectors ?
Best to all
Dana in CT ' 73 Fjord Blue CS w many CSL parts- I just finished a decent DIY interior refresh when this happened !!
Compression between 168 and 178 all cyls, spark present at each plug wire, fuel pressure 2.07 bar, ecu voltages partially checked showing correct temperature sensor resistances, correct ECU and Fuel Injector supply voltages, I think OK throttle switch performance ( tough to gauge w VOM only). NOID light test of fuel injectors showed NO flashing of lights to all injectors !!! Fuel injector circuit resistances tested from ECU : pin 3- 5 was 2.6 and pin 4-6 was 3.6 Pin 3 - 5 is in spec pin 4- 6 may be high dont know what to make of it. I have not yet checked the distributor trigger point system ( for the injectors). Fuel pump seems fine, but seems to run continuously. Fuel flows continuously to the rail when the pump actuates. I cannot figure out how to check the trigger signal for the injectors at the ECU and I do not have an oscilloscope, but I could take apart the distributor and measure cam excursion I guess and use VOM to look for rapidly fluctuating signal at he plug. Would appreciate any suggestions on the approach, I have the excellent jetronic.org web site and have been following those sometimes tough to understand instructions
Car has about 1000 mi since last valve adjustment. I have not done any ignition testing other than looking for spark, which again seem fine and strong. Plugs looked great but I need to test them individually ( used one plug only for testing for spark)
I am wondering how to find the fuel injector system relay ? From diagrams and the shop manual, and various wiring diagrams, I cannot yet figure out if there is a separate relay that may control fuel injectors ?
Best to all
Dana in CT ' 73 Fjord Blue CS w many CSL parts- I just finished a decent DIY interior refresh when this happened !!