86 Subaru XT turbo: Problems

[D_Rud]

I'm having some problems with my Subaru. It's not starting, not getting any fuel to the cylinders. Does anybody know if this model has a Fuel Injector, or Fuel Pump relay? I definitely have a fuel problem. Also, my engine monitor fuse keeps blowing. Any ideas?

[canajun2eh]

Fuel pump is controlled through a relay, which is in turn controlled by the engine control computer.

 

The relay coil sees constant +12 volts. The coil is connected to ground by the ECU, when the ECU sees a running engine or the engine is in "start" mode.

 

"Running engine" is indicated when the ECU sees tach pulses from the distributor.

 

You have to solve the blowing fuse first. Disconnect the ECU (located under the parcel shelf in the trunk). If the fuse doesn't blow with the ECU disconnected, you know that the ECU is bad.

[D_Rud]

Would I have to replace, or just repair the ECU?

Fuel pump is controlled through a relay, which is in turn controlled by the engine control computer.

 

The relay coil sees constant +12 volts. The coil is connected to ground by the ECU, when the ECU sees a running engine or the engine is in "start" mode.

 

"Running engine" is indicated when the ECU sees tach pulses from the distributor.

 

You have to solve the blowing fuse first. Disconnect the ECU (located under the parcel shelf in the trunk). If the fuse doesn't blow with the ECU disconnected, you know that the ECU is bad.

[canajun2eh]

Replace the ECU. Troubleshooting the ECU or finding the reason it's causing fuses to blow is beyond the capabilities of most people.

 

Before you do this, however, unplug the ECU, and see if the fuse still blows. If it does, you have a wiring problem.