jurer5 Posted April 26, 2014 Share Posted April 26, 2014 Just picked up a 1990 legazy auto for cheap. only got it cheap because a pack rat ate the engine harness up. so i got a new harness from a junk yard. replaced it and turns out it has been parked the past 4 years was im pretty sure the ignition control module went out. only cylinders 1 and 2 firing. not 3 and 4. well did research on here and check the continutiy between the coils and control module. good. changed coils. no change. so going to get a new on of those. but to be sure that it's not a ground issue i need help locating where this one ground goes. on the passenger side under the abs unit there are 2 grounds. one from the headlight harness that goes to body and the other one i can not find any place that it would hook up. can some on please point me in the right direction or picture. i got the manual with the ground locations but its so vauge it just doesn't help. thanks Link to comment Share on other sites More sharing options...
jurer5 Posted May 2, 2014 Author Share Posted May 2, 2014 No one has any ideas what that ground goes too? Link to comment Share on other sites More sharing options...
lmdew Posted May 2, 2014 Share Posted May 2, 2014 There are a couple of ground wires that come out of the main harness running under the radiator, they hook to the frame. Link to comment Share on other sites More sharing options...
Rooster2 Posted May 2, 2014 Share Posted May 2, 2014 Off the subject...........the car has been sitting for 4 years, recommend you add some Marvel Mystery Oil to the oil and gas. Drive appx 50 miles, then change the oil. MMO is a detergent product that helps remove sludge and carbon build up from an engine. Looks like nut shells piled up around your motor. Mice, rats, or squirrels can do that. Chewed up wiring most likely from mice. Motor looks clean otherwise. Hope you find the ground wires. Suggest you pull the spark plugs from 3 & 4 to check their condition, if you have not already done so. Link to comment Share on other sites More sharing options...
Gloyale Posted May 2, 2014 Share Posted May 2, 2014 The grounds on the frame don't affect the engine running. All ECU grounding happens at the bolt on the intake manifold. I'll bet it's just the coil Link to comment Share on other sites More sharing options...
willwright Posted May 3, 2014 Share Posted May 3, 2014 Generally speaking, if one end is connected to the body, then the other will connect to engine and vice versa, I have seen old dodge trucks require a ground to frame and an ground to body from engine.. wish my book had your yrs model included but you could sneak a peek at one at auto zone or invest 29 bucks in the book and have a very valuable resource in your hands. Link to comment Share on other sites More sharing options...
heartless Posted May 3, 2014 Share Posted May 3, 2014 Generally speaking, if one end is connected to the body, then the other will connect to engine and vice versa, I have seen old dodge trucks require a ground to frame and an ground to body from engine.. wish my book had your yrs model included but you could sneak a peek at one at auto zone or invest 29 bucks in the book and have a very valuable resource in your hands. A Subaru is not an old Dodge truck... you're comparing apples and oranges there. you can get wiring diagrams for just about any yr/model here: http://jdmfsm.info/Auto/Japan/Subaru/ After going out and popping the hood on my 90 Lego - of the two ground wires on the passenger side - one goes into the main harness under the radiator, the other runs up to the lighting harness (headlight/marker light). Hope that helps. Link to comment Share on other sites More sharing options...
lmdew Posted May 3, 2014 Share Posted May 3, 2014 Looks like the ground wire that comes off the ABS unit and grounds to the ABS mounting bolt to frame. Link to comment Share on other sites More sharing options...
heartless Posted May 3, 2014 Share Posted May 3, 2014 Looks like the ground wire that comes off the ABS unit and grounds to the ABS mounting bolt to frame. Sorry, but no... ABS ground is quite short - only about 3.5 inches long, is a much heavier guage, and bolts to the top of chassis as shown in this pic I just took from under the hood of my 1990 Legacy LS. I am aware that there were a couple of different ABS units in play during the early years of the Legacy, but from his pictures, we have identical ABS units. the two down on the side - bolted down together - go where I previously posted. Link to comment Share on other sites More sharing options...
jurer5 Posted May 5, 2014 Author Share Posted May 5, 2014 great thanks guys. this is just what i needed. got the 2 grounds from the headlight harness grounded just that one wire was a mystery. and the oil and fuel cleaner was the plan. just need to get it running first. the coil is good too, brand new. same with the ignition control module. still won't fire on 3 and 4. if i remove the spark plug wires to 3 and 4 there is no spark still. so got the wiring diagrams and check continuity from the coil plug to the ignition control module. all good. and the ignition control module to the ecu. also all good. Then check to make sure i had all grounds grounding out and proper power at the ecu connectors. All fine. So I ordered a ecu off ebay. hopefully That's the problem. I have no other ideas why 3 and 4 won't fire. Link to comment Share on other sites More sharing options...
Rooster2 Posted May 5, 2014 Share Posted May 5, 2014 great thanks guys. this is just what i needed. got the 2 grounds from the headlight harness grounded just that one wire was a mystery. and the oil and fuel cleaner was the plan. just need to get it running first. the coil is good too, brand new. same with the ignition control module. still won't fire on 3 and 4. if i remove the spark plug wires to 3 and 4 there is no spark still. so got the wiring diagrams and check continuity from the coil plug to the ignition control module. all good. and the ignition control module to the ecu. also all good. Then check to make sure i had all grounds grounding out and proper power at the ecu connectors. All fine. So I ordered a ecu off ebay. hopefully That's the problem. I have no other ideas why 3 and 4 won't fire. ECUs don't often break, but nothing is perfect, so hope a replacement unit solves your problem. Sounds like you have done a thorough job of checking everything else out. Good Luck. Link to comment Share on other sites More sharing options...
jurer5 Posted May 7, 2014 Author Share Posted May 7, 2014 so got the new ecu in. plugged in. started right up and firing on all cylinders. runs real good. so somehow the ecu crapped out but found no solid way to check where it was messing up too not fire 3 and 4. could have not been reading the crank, or cam sensors, ground crapped out inside ecu. who knows. but it runs good now and only with a canister purge valve solenoid code. 2 Link to comment Share on other sites More sharing options...
Rooster2 Posted May 7, 2014 Share Posted May 7, 2014 so got the new ecu in. plugged in. started right up and firing on all cylinders. runs real good. so somehow the ecu crapped out but found no solid way to check where it was messing up too not fire 3 and 4. could have not been reading the crank, or cam sensors, ground crapped out inside ecu. who knows. but it runs good now and only with a canister purge valve solenoid code. Good to hear that you got fire to 3 & 4. Gotta make you feel good. Link to comment Share on other sites More sharing options...
willwright Posted May 8, 2014 Share Posted May 8, 2014 glad to hear you got it fixed, my point about the grounds and compared to old dodge trucks was making sure all grounds were there. Wasn't saying they were the same lil. In should have made myself more clear about that, sorry if it sounded different. Link to comment Share on other sites More sharing options...
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