1988 740 Turbo ECU faults?? Injector problem still present....

Sep 7th, 2005, 05:37

How can I connect to the ECU to read the faults on my 1988 740 Turbo? Is there a plug or wires that I need to jumper or plug in to read the fault codes? I haven't been able to read any faults, but maybe I'm not connecting correctly.

My main problem is now that I have a constant current supply to the #2 injector, so I am flooding the #2 cylinder and consequently, running on 3 cylinders. I've changed the ECU, with no change to the situation. I've checked the harness for grounds and haven't found any. I've checked for spark at each plug and I've verified that the fuel injectors are spraying plenty of fuel.

The other injectors are pulsing, but the #2 is constantly spraying fuel....faulty ECU? Faulty relay? Help!?!?
-Walter

Sep 8th, 2005, 07:36

all injectors get ECU pulse (negative!) via same ECU pin...only 4 resistors at the positive side of injectors - current to them via same wire too...faulty injector???

Sep 9th, 2005, 05:35

I'll check that again, but I think the injectors are all fine. I have traced out the wiring and I now suspect what looks to be a:
"Trip Power Computer Control Unit" Volvo part #899931 1323592-1 12 V/40amp.

Does anyone have any experience with this? Could this be causing a constant current supply to injector #2?
-Walter

Sep 7th, 2005, 05:37	#1
Walter Guest Location:	1988 740 Turbo ECU faults?? Injector problem still present.... How can I connect to the ECU to read the faults on my 1988 740 Turbo? Is there a plug or wires that I need to jumper or plug in to read the fault codes? I haven't been able to read any faults, but maybe I'm not connecting correctly. My main problem is now that I have a constant current supply to the #2 injector, so I am flooding the #2 cylinder and consequently, running on 3 cylinders. I've changed the ECU, with no change to the situation. I've checked the harness for grounds and haven't found any. I've checked for spark at each plug and I've verified that the fuel injectors are spraying plenty of fuel. The other injectors are pulsing, but the #2 is constantly spraying fuel....faulty ECU? Faulty relay? Help!?!? -Walter

Sep 9th, 2005, 05:35	#3
Walter Guest Location:	RE: 1988 740 Turbo ECU faults?? Injector problem still present.... I'll check that again, but I think the injectors are all fine. I have traced out the wiring and I now suspect what looks to be a: "Trip Power Computer Control Unit" Volvo part #899931 1323592-1 12 V/40amp. Does anyone have any experience with this? Could this be causing a constant current supply to injector #2? -Walter

Sep 8th, 2005, 07:36	#2
mgarageu Guest Location:	RE: 1988 740 Turbo ECU faults?? Injector problem still present.... all injectors get ECU pulse (negative!) via same ECU pin...only 4 resistors at the positive side of injectors - current to them via same wire too...faulty injector???

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)