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Hi everyone

I'm working on a well used 90 Loyale Turbo. Installed a used (low mileage) motor from Japan. Got everything swapped between the two so it will run. Had it out on the road and everything working fine for about 3 miles and then it seemed to run short of gas, it would idle and then a short burst of power and back to idle. It finaly quit. I could start it then it would die, now it it won't start. Jumperd the fuel pump, it works but no 12v back there. Been two days looking for the fuel pump relay,no find, can see it on some wiring diagrams. Fuse OK. What am I missing? Thanks for any help

Crupper

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Fuel pump relay is under the dash, above the ECU.. there are two relays there one is ignition and one is fuel pump.

 

Are there any error codes showing on the ECU?.. is there a light at all?

 

And one more thing.. this may sound really weird... check your horn fuse :)

 

PS.. welcome to the board.. we'll get you fixed up in no time. Worst case is you might have to have one of the WA or OR boys come help you out... Theres lots of them here.

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Thanks, but what is the ECU? I have the owners manual and a Haynes repair manual and it isn't mentioned in either. There is a picture of a ECM in fig.10.21 "Verious under-dash electrical unit locations". It also shows a picture of a Fuel pump control unit, is there a chance it might be the cause of no juce to pump? I haven't been under the dash yet this AM as I've got to dig a grave for the neighbors old dog, she is putting it down today. Many tears. I'll get back to Soobin later today. Is it possible for the pump to run and still not build enough pressure to keep the motor running? I'll pickup a new filter today also.

 

Crupper

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ECU.. ECM.. same thing, different terminology.

 

I don't think there is a seperate Fuel pump control unit on EA82 cars. Its all controlled by the ECU(ECM) in combination with the distributor.. if the distributor isn't turning, the fuel pump will only run for about 1.5 seconds.. long enough to pressurize the system.. That may be why you are not seeing power at the fuel pump. Probably not, but possibly.

 

The manual you have isn't very useful for this stuff on a turbo car (assuming its the same haynes manual I have).. Most of the haynes manual are more geared toward EA81 stuff.

 

Under the dash, there are 2 green connectors, plug them in and turn on the key. you should hear the fuel pump cycle on and off in 1.5 second intervals with those plugs connnected. If there are active error codes, they will also display on the small LED on the front of the ECU at that point.

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the fuel pump and ign relays are on a little bracket on the steering column itelf, just above the ecu(ecm) 3 nuts hold it up, one of them may have a ground wire(either there or on the bolt for the column itself

 

the distributor sends a signalt to the ecu for the fuel pump to operate while its spinning. there are also green test mode clips under the dash, plug them in, and the fuel pump should cycle on and off when the key is in RUN pos.

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OK Found the lost ECU, key on and it blinks 3 times then pauses and 3 times again, is it telling me something?

I plugged the green connectors together. I run a wire from the hot side of the pump to a 12v light that I had for other testing, to the front seat area, so I can tell when the pump is on,turned key to run the light blinked on & off like you said it should, Checked to be sure that the pump was actualy running, started the motor, it ran (lights stayed on) till it run out of gas and then went back to on & off again. I could hear the relay working so it is OK. Did this several times with same results. Filter seems to be handling enough gas to run my 427 SS so it must be the pump that can't keep up, Huh?

Crupper

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another thing to check would be the temp sensor for the ecu. not to be confused with the temp sending unit for hte gauge, the one to check is on the back side of the intake near the turbo. you will have to remove the upper plenumn(undo the hose clamps, but you can leave the hose underneath connected) it has a brown clip that looks like the connectors for the injectors.

 

the haynes book will have the testing procedure and the resistance values for this sensor. if the sensor is out of whack, the car will start and run while cold, but onece it warms up and goes into open loop mode, it will throw off the fuel metering.

 

sounds like the car started and ran till it warmed up? how long does it run before it dies? somtimes somply cleaning the connector itself can cure the problem

 

but you may consider replacing the sensor anyway for safe measure, they should be 17 bucks or so, and may be listed as a nissan part(as was alleyboy's)

 

somebody around here should have a part number for the ecu thermo sensor

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Hey Cupper

 

Two ideas for ya.... I believe that there is a second fuel filter under the car near the pump. And, I'd tee in a pressure gauge where the fuel line connects to the fuel rail, the book should give you a minimum spec.

 

Gary

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There is only one fuel filter, its behind the drivers side strut top. Try releasing the gas cap. Really. See if it runs for more than 30sec. If the pump is cycling and you have pressure past the filter, something else is going on. The blinks come in 2 different lengths, short and long. You may want to recheck this.

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