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Fuel Injector only works while cranking


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Hello to all! I have got a good one for you, I don't know what else to do. I picked up a 93 Subaru Loyale Wagon for next to nothing with a junk engine. I went to Pull n Save, pulled an identical motor - SPFI EA82.

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This car had a push button 4wd 5 speed and while I was at it I swapped in a d/r 5 speed I had around. Everything is hooked up now and engine will start but as soon as it does so it immediately dies. It will continue running good on starting fluid but nothing more. I sighted down the throttle body and could see that while I was cranking the injector was spitting out fuel but as soon as it caught, no more. I hooked up a noid light and could see that the signal would pulse while cranking but as soon as the car would start, the light would fade to a very dim constant.

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Here as possibly some related issues

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The Loyale has a silver ECU but the engine is from an unknown year (stupid me for not writting it down. The intake manifolds look identical however and everything plugs in right.

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When the battery is hooked up the tail/parking lights are lit. The only way to turn them off is to pull the fuse but the funny thing is that the tail light fuse doesn't do it, instead the only fuse that shuts them off is the door lock 20A fuse.

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The other thing is that the key won't trigger the starter. I tested and found that when I turn the key to start the point on the switch itself reads 12v but not at the starter end. I tested for continuity between that column end of the wire and the starter end and there is none. Is there a lockout circuit like a neutral safety? The wiring diagram only shows one for automatics. I haven't hooked up the tranny harness. The car harness to the tranny consists of a square 4 wire white one and a 2 wire black one. The tranny itself only has a round 4 wire white one. I assume that I can snip the wires and just match them up. I also assume this doesn't have the neutral switch but from my reading that shouldn't affect starting. This car doesn't have cruise so is there a way to hook up that neutral switch to the clutch like some say?

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Well thanks for all your help, I am really wanting to get this thing on the road and this is all that is stopping me. You guys are a great resource and I hope I have given a good enough description.

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Everything is hooked up now and engine will start but as soon as it does so it immediately dies. It will continue running good on starting fluid but nothing more. I sighted down the throttle body and could see that while I was cranking the injector was spitting out fuel but as soon as it caught, no more. I hooked up a noid light and could see that the signal would pulse while cranking but as soon as the car would start, the light would fade to a very dim constant.

 

Sounds like a possible fuel issue to me. Like the pump isn't running immediately after start....

 

The Loyale has a silver ECU but the engine is from an unknown year (stupid me for not writting it down. The intake manifolds look identical however and everything plugs in right.

 

They will all run the engine the same. The differences are not significant to your problem.

 

When the battery is hooked up the tail/parking lights are lit. The only way to turn them off is to pull the fuse but the funny thing is that the tail light fuse doesn't do it, instead the only fuse that shuts them off is the door lock 20A fuse.

 

Flip the parking light switch on top of the column. It's a Subaru thing....:rolleyes:

 

The other thing is that the key won't trigger the starter. I tested and found that when I turn the key to start the point on the switch itself reads 12v but not at the starter end. I tested for continuity between that column end of the wire and the starter end and there is none. Is there a lockout circuit like a neutral safety? The wiring diagram only shows one for automatics. I haven't hooked up the tranny harness. The car harness to the tranny consists of a square 4 wire white one and a 2 wire black one. The tranny itself only has a round 4 wire white one. I assume that I can snip the wires and just match them up. I also assume this doesn't have the neutral switch but from my reading that shouldn't affect starting. This car doesn't have cruise so is there a way to hook up that neutral switch to the clutch like some say?

 

Manuals don't have crank inhibitors. There are no fuses, switches or relays in the crank circuit of a manual transmission EA82. Your ignition switch is likely bad.

 

There is a start signal wire (green with yellow stripe IIRC) that signals a start sequence in the ECU. That may be related to your fueling issue but it's hard to say. Just hooking up a crank button will not signal a start to the ECU. It's hard to say how much that actually matters in practice though. The line should be hot in CRANK only. It's powered by the ignition switch itself.

 

Are all your sensors hooked up? The engine will have a very hard time starting without a MAF, or the CTS..... any codes from the ECU?

 

GD

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Thanks for your reply, sounds like some good ideas

 

Sounds like a possible fuel issue to me. Like the pump isn't running immediately after start....

Would I test this with a pressure tester? I can hear the pump cycle on after turning the key on but then it stops. I did check for pressure (the wrong way by pulling a line off the filter and getting 6 foot spit of fuel) Is there any reason for it to run the pump for start but not run? The signal itself goes away for the injector, would that quite because it senses no fuel pressure?

 

 

 

 

 

They will all run the engine the same. The differences are not significant to your problem.
Oh good

 

 

Flip the parking light switch on top of the column. It's a Subaru thing....:rolleyes:
oops how embarrasing :)

 

 

Manuals don't have crank inhibitors. There are no fuses, switches or relays in the crank circuit of a manual transmission EA82. Your ignition switch is likely bad.
Thats what I thought but I did test for a 12v signal at the solder joint of the ignition switch and it has it when in the start position so I assume it is ok. The wire I found that went to the starter was a large ga black with red strip. I found a wire of same ga and markings at the start post of the ignition switch and did a continuity test at both points and it failed. Strange that the wire would fail but could that be it, and if so what is the solution? If you still think it is the switch, how can I test it better?

 

There is a start signal wire (green with yellow stripe IIRC) that signals a start sequence in the ECU. That may be related to your fueling issue but it's hard to say. Just hooking up a crank button will not signal a start to the ECU. It's hard to say how much that actually matters in practice though. The line should be hot in CRANK only. It's powered by the ignition switch itself.
Thats interesting How would I test for that to see if it is actually making it to the computer?

 

Are all your sensors hooked up? The engine will have a very hard time starting without a MAF, or the CTS..... any codes from the ECU?

Yea, all the sensors are hooked up and it will start with no problem it just won;t keep it up. The check engine light isn't on but how do you check for codes. I know about the blinking light and have the panels off but which connectors need to be hooked up or disconected? those are the ones underneath the hood release handle right?

 

Thanks for your patience.

 

Drew

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Would I test this with a pressure tester? I can hear the pump cycle on after turning the key on but then it stops. I did check for pressure (the wrong way by pulling a line off the filter and getting 6 foot spit of fuel) Is there any reason for it to run the pump for start but not run? The signal itself goes away for the injector, would that quite because it senses no fuel pressure?

 

The fuel pressure regulator is mechanical. The ECU has no way to sense the pressure.

 

The ECU will only run the fuel pump if it senses a tach signal, durring cranking, and for a short interval when the key is turned to run. You may have a problem with the tach signal to the ECU.

 

Thats what I thought but I did test for a 12v signal at the solder joint of the ignition switch and it has it when in the start position so I assume it is ok. The wire I found that went to the starter was a large ga black with red strip. I found a wire of same ga and markings at the start post of the ignition switch and did a continuity test at both points and it failed. Strange that the wire would fail but could that be it, and if so what is the solution? If you still think it is the switch, how can I test it better?

 

Wire colors tend to change as they pass through different portions of the harness. Test for 12v at the wire to the starter solenoid when the switch is in the crank posistion.

 

Thats interesting How would I test for that to see if it is actually making it to the computer?

 

It should be a thin gauge wire on the body side of the ignition switch connector. I can't recall the pin on the ECU right now, but either someone else will know, or I can look it up. There's also PDF's around on various sites that can help you with that, and other information.

 

Yea, all the sensors are hooked up and it will start with no problem it just won;t keep it up. The check engine light isn't on but how do you check for codes. I know about the blinking light and have the panels off but which connectors need to be hooked up or disconected? those are the ones underneath the hood release handle right?

 

Yeah - green for test mode, and black for read memory mode.

 

GD

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The ECU will only run the fuel pump if it senses a tach signal, durring cranking, and for a short interval when the key is turned to run. You may have a problem with the tach signal to the ECU.

 

When I was trying to start the car simply by turning the key, it would make a 3 part clicking sound I think. On the third try of turning and nothing happening, the tachometer would peg all the way up and then come back down. Could that mean anything? Also How does the ECU know it is cranking?

 

 

Wire colors tend to change as they pass through different portions of the harness. Test for 12v at the wire to the starter solenoid when the switch is in the crank posistion.

 

Tested that and there is 0 voltage at the starter solenoid although there is voltage at the column.

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Wiring in a pushbutton starter for a Subaru is nothing new, could be you need to do so.

 

 

But the bigger issue is the inabilty to keep running. Seems like it could be related, but then again maybe not. I'm thinkin some kind of power supply issue. If it was a disty issue, it wouldn't keep running on starter fluid.

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