93 Impreza not starting

[Dangerdave]

Hi Guys,

 

I've got a 93 AWD Impreza with a 2001 legacy gt engine swap running on the 1.8 liter ecu. The car has been running really well until today. It turned over but showed no signs of starting. I don't think it's cold enough up here yet for water to have frozen in the lines. It will run on quick-start for a few seconds before quitting.

 

Would the fuel pump be the most likely culprit? Can I run-down any other possibilities before removing the tank? It exhibited no other symptoms until today.

Any help would be appreciated.

Thanks, Dave

[lmdew]

Any CEL or codes in the computer. It could be most anything.

 

Check for Spark

Check fuel pressure

Can you hear the pump run, you don't drop the tank the pump is pulled from the top access cover, Under the back seat or in the trunk.

[Dangerdave]

Lots of spark. No CEL's. How would I check for fuel pressure? I've seen the access panels under the back seat. Is it possible to do from there?

[lmdew]

Unplug the fuel pump under the seat, crank the car for 20 seconds or so to release some of the fuel pressure.

 

You will need a 5/16" tee fitting, about 6" of fuel line.

 

Go on the engine side of the fuel filter in the engine compartment and tee in the fuel pressure gauge.

 

Hook up the fuel pump connector and crank the car over. You should see fuel pressure rise as the system pressurizes.

 

I don't have the exact PSI but anything over 30 should be good.

[idosubaru]

did you check the timing belt?

 

the quick cheezeball fuel test i do is to just pull the fuel line off the fuel filter in the engine bay and turn the key over. if fuel comes out, your engine has fuel at least. could be low but i'm used to seeing far more pumps that don't work than ones that have low output.

[Cougar]

If you listen carefully you should be able to hear the fuel pump run for a couple of seconds when you turn the key from OFF to RUN. If you do hear it then at least power is getting to it. The pump circuit may be controlled by a switched ground connection through the ECU. The circuit can go bad in the ECU. There is a fuel pump relay also that should be checked if the pump isn't getting voltage to it.