matt4irish Posted December 10, 2016 Share Posted December 10, 2016 This is really baffling me. Could use help. Pulled main relay and it bench tests fine. Had a crank sensor code, replaced with new. Timing covers off and all looks intact. Can see OBDII readout at port, but when I test probe connectors at ECU per FSM, I am not seeing power consistently at PIN 1 and 2 and there is no ground at 19. Cleaned as many grounds as I could find. Have new battery. Amazingly, I can hear fuel pump run on key turn and the main relay energizes the proper five ports. Have 12V to ignition control and coil pack, but no pulse. Noid light will not come on at any time at injector 1. Does this sound like failed ECU? Thanks, Matt Link to comment Share on other sites More sharing options...
lmdew Posted December 10, 2016 Share Posted December 10, 2016 Subaru Crank Sensor? Also check the Cam Sensor. 1 Link to comment Share on other sites More sharing options...
matt4irish Posted December 11, 2016 Author Share Posted December 11, 2016 Yes OEM Crank. Both sensors show in spec. No spark and nu pulse for injectors plus the ECU power issue. Could ECU be shorted and only allowing display? Car cranks fine from starter, no evidence of timing slip. Link to comment Share on other sites More sharing options...
montana tom Posted December 11, 2016 Share Posted December 11, 2016 Little more info please. Is this a 2.5 dohc ? Was car running fine then just stopped ? Was any work performed ? Still sounds like cam/crank sensor to me ... If you have access to known working sensors (like your buddys car) you could try switching. You said timing covers are off ? Or just the outer covers ? You may need to confirm all the timing marks. While you are in there inspect the ears on the crank sprocket make sure all is good with it. Link to comment Share on other sites More sharing options...
matt4irish Posted December 11, 2016 Author Share Posted December 11, 2016 It is a 2.5 DOHC, all stock. Car was running perfect, started loping a bit at highway speed and then stopped. The initial stop came just after stopping at a stop sign. Would not restart. Battery also died during short strap tow (in fwd). Recharged battery, car fired right up. Drove perfect again for another mile, but started bucking. Then died and could not restart. Left car until next evening. Next night, car started long enough to drive up ramps to tow trailer. Towed home (on trailer) and battery was too weak to power starter so had to push to rolloff. Replaced battery and car started to move to driveway. but have not been able to start since. Car turns fine (doesn't make sounds like off timing), but as mentioned, no spark from coils to plugs. Test light shows constant light on the side terminals coming into coil (no pulse). Also noid light does not light at injectors. You are correct that I only have side timing covers off at this time. Will pull the center one next and verify the positions. I tried to clean grounds as this car has seemed to be hard on batteries in past. Starter is running strong and accessories seem to run well too. No codes now, but I doubt it would throw a code while just cranking. Link to comment Share on other sites More sharing options...
1 Lucky Texan Posted December 11, 2016 Share Posted December 11, 2016 I like the CAM sensor suggestion. far outside possibilities; fuel pump fails when it gets warmed-up, exhaust blockage Link to comment Share on other sites More sharing options...
matt4irish Posted December 11, 2016 Author Share Posted December 11, 2016 Will a failed cam sensor stop it from any spark and from any fuel injector signal? Is there a good way to test a cam sensor? Thanks! Link to comment Share on other sites More sharing options...
lmdew Posted December 11, 2016 Share Posted December 11, 2016 Yes, if you need a couple of spare cam and Crank Sensors, I can send them to you. Friday, I'll be flying through ORD. Larry Link to comment Share on other sites More sharing options...
matt4irish Posted December 12, 2016 Author Share Posted December 12, 2016 Is there a truly reliable way to test a cam sensor on the 96 Outback? Link to comment Share on other sites More sharing options...
montana tom Posted December 12, 2016 Share Posted December 12, 2016 Testing never has worked for me, its always been faster /easier to just to locate a known working one or pop both sensors out from a wrecking yard. If one of those sensors has failed it will not send a spark signal. If you had broken wings on the crank gear it would get a spark and try to run but not succeed. Have you tried a different coil ? 1 Link to comment Share on other sites More sharing options...
matt4irish Posted December 12, 2016 Author Share Posted December 12, 2016 OK. Would that also explain the no noid ligght from the injectors? Link to comment Share on other sites More sharing options...
matt4irish Posted December 12, 2016 Author Share Posted December 12, 2016 I agree, testing has always shown them good. Link to comment Share on other sites More sharing options...
matt4irish Posted December 12, 2016 Author Share Posted December 12, 2016 So, would bad cam sensor shut down both coil and injectors? The no signal from noid light (won't light at all) is what's throwing me on cam sensor. Clearly no spark, but no spark and no noid light are they both symptoms of failed cam sensor? Link to comment Share on other sites More sharing options...
montana tom Posted December 12, 2016 Share Posted December 12, 2016 Fact, If the computer can't sense the cam it can not signal the injectors. As far as the spark... I'm guessing here but i suspect the computer wont signal the coil at that point either. Link to comment Share on other sites More sharing options...
matt4irish Posted December 12, 2016 Author Share Posted December 12, 2016 Thanks guys. Got center timing cover off (ordering new bolts as these are rusted and starting to become a pain to get out). all timing marks spot on. Appreciate the help. Will post outcome after cam sensor replaced. Link to comment Share on other sites More sharing options...
matt4irish Posted December 12, 2016 Author Share Posted December 12, 2016 the injector noid light confuses me because every video I show shows th noid light constant on until started when it starts blinking. Makes me suspect improper voltage at mine as never get any light or our ours just different where the light only blinks as it gets the injector pulse (default no power, powered for pulse)? Haven't used noid lights in past, so want to make sure I am doing this part right! Link to comment Share on other sites More sharing options...
matt4irish Posted December 13, 2016 Author Share Posted December 13, 2016 OK, replaced cam sensor. Still no spark and no fuel injector pulse. HELP!!! Link to comment Share on other sites More sharing options...
john in KY Posted December 13, 2016 Share Posted December 13, 2016 Noid light will not come on at any time at injector 1. Not sure about this but thinking the injectors receive 12 volts (not from the ECU) and the circuit is completed at the ECU, the ground. If I am correct, then the noid light should show a solid light even if the ECU is bad. Won't flash. Any chance the problem is a blown fuse? Sounds like the problem is the injectors are not receiving a 12V signal. Link to comment Share on other sites More sharing options...
matt4irish Posted December 13, 2016 Author Share Posted December 13, 2016 Interesting you say that because when I probe the injector sensor, I am seeing the positive charge (12V full signal) on the yellow wire coming into injector #1 whether the ignition is on or off, but there is no ground signal on the other wire. That would explain why the noid is not lighting. If I use my ohmmeter and connect that brown wire terminal direct to a known chassis ground, it does not show continuity, so the ground must be lost assuming that yellow is positive and brown is supposed to be ground. So, it appears there is a lack of proper ground somewhere. Does that ground come from the ECU or elsewhere? Link to comment Share on other sites More sharing options...
matt4irish Posted December 13, 2016 Author Share Posted December 13, 2016 I had also probed the ECU prior in terminal 19 per the FSM which is supposed to be ground and it lacks continuity to known chassis ground. Where does the ECU ground on this 96 Outback 2.5 DOHC? Link to comment Share on other sites More sharing options...
matt4irish Posted December 13, 2016 Author Share Posted December 13, 2016 On the ECM, I am seeing + 12V power on terminal 1, but no - continuity on terminal 19. Makes me suspect ECM grounding. Again where does the ECU 19 wire ground to? That may be the broken link. Link to comment Share on other sites More sharing options...
matt4irish Posted December 13, 2016 Author Share Posted December 13, 2016 FSM shows 17, 18, 19, 20, 20, 42, 46, 69, 94, and 95 from the ECM all should chassis ground. I will go check each of them now. Still anxious to find out where those wires actually ground in the car. Link to comment Share on other sites More sharing options...
matt4irish Posted December 13, 2016 Author Share Posted December 13, 2016 Will now I am not seeing power on terminal 1 of ECU. Link to comment Share on other sites More sharing options...
matt4irish Posted December 13, 2016 Author Share Posted December 13, 2016 All of the ECM grounds are good!!! The power loss at the ECU is definitely the issue. What conditions must be met for the ECU to get power? I am still trying to understand the main relay's role. I know that leads 5 and 6 are constant 12V from SBF 2 which is good. And that ground is on lead 1 which is good. I know that lead 2 on the main relay goes to or from the ECM and connects to terminals 1 and 2 of the ECU. What actually energizes the main relay as I believe this is what sends power to the ECU and I think this may be my gap. I tried the FSM bench test for the main relay, Power to 1 and 2 and verify that there is 12V at all 5 terminals. It tested fine, so either I have a bad wire between the relay terminal 2 and the ECU terminals 1 and 2 OR the test is failing to properly identify a main relay fault. Any ideas? Link to comment Share on other sites More sharing options...
matt4irish Posted December 13, 2016 Author Share Posted December 13, 2016 Last post for tonight. FSM says to test with ECU disconnected. No signal on 1 or 2 of the ECM connection. However, if I reconnect and backprobe 1 and 2, I do see 12V, Is this a main relay issue or an ECU issue? Link to comment Share on other sites More sharing options...
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