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2000 Outback 2.5L 5spd
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Discussion Starter · #1 ·
I am new here, but have had the 2000 Outback since 2007. I have a 2001, 2003 and a 2004 Outback for parts so I am sort of stuck with this model. It has been a good car. I recently did an engine swap. I put the engine from the 2004 EGR (higher milage but better head gaskets than the old one had at 333,xxx) into the 2000. That engine had run just fine a year ago before the alternator seized. My old engine was still running before I took it out. The new engine will turn over, but won't start. I checked spark plugs, coil pack, visual spark check, timing belt moving driver's side of engine, (It will puff a bit on starter fluid) and changed the fuel pump yesterday.
Now I realize that when I turn the ignition on: the fuel pump runs the 2-3 seconds to prime the system, but does not turn back on when the starter is engaged. What controls the 2-3 second run, and turning back on for the starter and running mode? The ECU?
 

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Now I realize that when I turn the ignition on: the fuel pump runs the 2-3 seconds to prime the system, but does not turn back on when the starter is engaged. What controls the 2-3 second run, and turning back on for the starter and running mode? The ECU?
Yes, the ECU in both cases.

When the ignition switch is turned to the On position, the ECM activates the fuel pump relay for the 2-3 seconds, as noted. When the ignition switch is then moved to Start, in addition to powering up the starter motor, battery voltage from the Start position on the ignition switch is connected to the ECM, at terminal 28 of connector B135. This signals the ECM that starting has been initiated (or at least selected on the switch). The ECM again energizes the fuel pump relay, turning on the fuel pump. The ECM then monitors the engine sensors, and once apparent the engine is started it locks the fuel pump relay to stay on even when the ignition switch is released back to On. The pump then stays on until the ignition switch is turned from On to Off or if the engine stalls. If the engine does not start up, when the key is released from the Start position, back to On, the pump relay is turned off as well.

Because everything related to the fuel pump and the starter motor seems to be working, what might be missing is the Start-status signal to ECM terminal 28 of connector B135. That would be an odd fault. It could be just a bad contact at the ECM connector. Perhaps remove and reinstall the connectors at the ECM.
 

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Any trouble codes?

The ECU will not turn the fuel pump on while cranking if the crank sensor/circuit has failed (could have been damaged during alternator replacement).

I suppose it's possible that the ECU could have been damaged if the alternator was badly overcharging before seizing, but this is a pretty big stretch.
 

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Wait, I've read your post a few times and I'm still not clear. Did this "new" engine ever run in this car?

If not, did you check or swap the crank and LH cam sprockets? There are a couple tone wheels for crank and cam sensors, and fairly strange pattern to what used what, so best practice is to swap them when swapping an engine.
 
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Old skool thought....when cars went to electric pumps, one of the easy things to do to protect against low oil was to cut off the fuel pump if the oil pressure dropped off. This could be done via relays or ECUs.
Where I am going is the two engines may have different oil pressure sending units (one for a simple light, other for a gage). Be sure to use the sending unit that came with the car.
 

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If not, did you check or swap the crank and LH cam sprockets? There are a couple tone wheels for crank and cam sensors, and fairly strange pattern to what used what, so best practice is to swap them when swapping an engine.
Good point. I haven't seen anything confirming that with the wrong, or missing, crank or cam signal the ECM might not turn on the pump while cranking. But if that's the case, it's certainly a possibility here.

This thread involves swapped engines where the signal pickup rings on the sprockets caused spark problems. Perhaps there was a fuel component as well.
 

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Discussion Starter · #7 ·
I'll have to check into these suggestions and get back to you all. No, this engine never ran in this car before. The only trouble code I had on the old engine, at the very end, was a cylinder 4 misfire (black spark plug, and at the same time the wire boot was loose on cylinder 3, It was running on 3 cylinders on start up. Boiled over later that day. Ran fine otherwise. Didn't like to keep coolant in the engine for a while. Pushing more into expansion tank than receiving back.) I'll check into potentially damaging anything when changing the alternator. I have an ECU in a parts car that took the same non-egr engine. I was wondering about using a spare fuel pump plug to temporarily wire up a forced running of the pump.
 

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Old skool thought....when cars went to electric pumps, one of the easy things to do to protect against low oil was to cut off the fuel pump if the oil pressure dropped off. This could be done via relays or ECUs.
Where I am going is the two engines may have different oil pressure sending units (one for a simple light, other for a gage). Be sure to use the sending unit that came with the car.
All Subarus of this vintage only had an oil warning light, using the same switch. None of which are wired to the ECU or have any effect on fuel pump operation.
 

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I'll have to check into these suggestions and get back to you all. No, this engine never ran in this car before. The only trouble code I had on the old engine, at the very end, was a cylinder 4 misfire (black spark plug, and at the same time the wire boot was loose on cylinder 3, It was running on 3 cylinders on start up. Boiled over later that day. Ran fine otherwise. Didn't like to keep coolant in the engine for a while. Pushing more into expansion tank than receiving back.) I'll check into potentially damaging anything when changing the alternator. I have an ECU in a parts car that took the same non-egr engine. I was wondering about using a spare fuel pump plug to temporarily wire up a forced running of the pump.
I bet you have the wrong sprockets on there.


 

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Discussion Starter · #10 ·
I bet you have the wrong sprockets on there.


You were right about the sprockets. Wouldn't have figured that one out without your help. Thanks.

Finally got it started a few minutes ago. (not properly together, just ran for 8 seconds without timing cover, belts, or rad)

First I tried to see if I could just swap the ECU. The 2000 has 3 ECU connectors, the 2004 has 4. I got the sprockets swapped. Then on re-assembly the bolt hole for the lower timing belt bearing on the passenger side stripped out. Must have been previously weakened. Had to buy an over-size bolt and blind end tap. Then the 90 drill I had bought hoping to fit in the 9 1/2" between bolt hole and AC rad wouldn't line up. Ended up doing it "really by hand" with a pair of vise grips holding the bit. Then grinding down the bolt head to fit the 16mm max socket size inside that bearing. Then over size the mounting hole in the bearing. Got it tightened down this time. Then the crank gear wasn't in all the way when I tried to start it. It was running against the tensioner bearing. When I figured that out, and pushed it back under the crank sensor, then the engine started on the next try. Finally! Thanks again.
 
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