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ChrisInVT

Forever cranking, never starting. No spark & ECM not communicating

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Now thats a clue! Bad grounds cause all kinds of hell. ECM grounds to the block on the intake manifold. Probably top passenger side near the ignition coil on that year. Should be several black or brown wires coming together at one point. It could also be low down behind the #4 injector on the back of the manifold drivers side.

You can also check the ground points at the lower corners of the center dash console. One on either side down low below the level of the change tray / cup holder in front of the shifter.

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The fuel injectors aren't firing still, but I do have spark and can pull codes off the ECM (getting code P0505 now, I removed the IAC and cleaned it, checked continuity to the ECM and 12v on the plug, but the code is still coming up). The car will run off starting fluid, so now I just need to figure out why the injectors aren't firing.

I haven't traced the ground wire back yet, for now I just have another wire plugged in and grounded while I continue to troubleshoot.

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You have proved that the ground wire going to the OBD2 connector is defective and has a high resistance to chassis ground, good work. I'm not sure where that ground bonds to but I will try to find out. I suggest you clean all the grounds you can find under the hood, especially the battery to chassis ground.

 

Even though the fuel pump is working there still can be a problem with the Main Relay. As I mentioned earlier, the relay has two sets of contacts,not just one set like most relays.

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I've removed the main relay (what a job that was) and jumped both sets of terminals with the same issues. I've also tested downstream of it, and am getting good voltage at the ECM and at various sensors that the 2nd terminal powers. Just gotta track down this fuel injector problem now.

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Here's what I'm thinking, wherever the ground for the OBD2 port has failed, the other end will probably be for the ECM's injector pulse to ground. Going to trace that wire and see what I can find, wish I had my tone generator from work - that would make my life a bit easier.

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If you dont already have one, invest in a Power Probe.  If you cant afford one, borrow one from a friend.  it makes these electrical issues so much easier and saves a ton of time. 

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Ground on the OBD2 port came back all by itself while I was checking grounds at the ECM. The Black/Yellow wires have NO chassis ground. I made a jumper from the Black/Red wires on the ECM to the Black/Yellow wires and the car fired up. 

 

 
The fuel pump relay was clicking on/off at idle in regards to the RPM of the engine, if I give it more throttle it stops clicking. That seemed to be a problem with the ECM from the 2.2 Outback, plugging my ECM back in solved that issue. Car has been idling now for the past 5 minutes, only code I'm getting is P0462 FUEL LEVEL SENSOR CIRCUIT A LOW INPUT. That explains why my gas gauge only half works.

The FSM is useless telling me where these grounds run back to, and all the pinouts for the ECM that I'm finding, are completely wrong in regards to what goes to where. I'm going to splice into the Black/Yellow wires, solder in and create my own chassis ground on the mounting plate for the ECM. I'll look into finding where the ground went bad later when I tear out my interior to replace my parking brake cables. I'm going to rip the interior out of the 2.2 Outback and strip that car down to a shell, so then I'll know where all the electrical connection are for me to find this bad ground.
Edited by ChrisInVT

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Pretty much all of the ECU grounds go back to the intake manifold with the main engine harness. The whole bottom row (4 pins) of one of the big connectors at the bellhousing is ground wires for the ECU.

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My factory manual is showing me exactly where the grounds are tieing to. According to my info it shows the ground for the data port, the fuel gauge sensor, and some ECUs grounds tie to connector B22/E3 and go to a common ground point called GE, which tie to a point on top of the engine area, about in the center, on the rear end of it. All the wires are blk/red and also bond to a black wire at the engine ground point, which also runs to the ECU. It looks like fixing that ground point will also solve all the other problems you are having.

 

My info shows the blk/'yel grounds tie to the same common point but are tie together seperately from the b/r wires. So if the engine ground point is ok then the trouble is most likely at connector B22 where they all tie through to the ground. Seperating and reconnecting the connectors may fix the problem.

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