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Help please! 96 outback stall, no start, no spark, no injector pulse


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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

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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. 

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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.

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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 ? 

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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!

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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. 
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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?

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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? 

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