wont start , bad connection ?

[gtrx7]

Hi everyone im new here and have joined to see if any one can help with a starting problem i have.

The car is a 1994 wrx JDM spec (imported into uk)

the car has drove great , i just had a new exhaust and sparkplugs put on / in.

2 days later i did a 30 mile trip , pulled up on the drive came out and it just turned over without starting.

got my friend round we pulled a few fuses (all were fine) still cranked over but wouldnt start, left it for 10 mins and turned the key and it fired instantly

drove the car to the shops , got some bits n bobs and went home

next day same thing, and hasnt started since.

their is no alarm or immobiliser installed
their is an hks turbo timer (incase thats something to do with it)

im sure it has to be a loose connection or bad earth somewhere , but if someone could point me in the right direction of what to check that would be much appreciated as its a real head scratcher for me.

plugs are fine
fuel pump makes a noise when key is turned
battery is fully charged
no obvious connectors loose or missing
has over 1/4 tank of fuel (when it first did it i thought it was out of fuel so put around 20 litres in)

[SD_GR]

Is there a distributor? If so check the main connection to that.

[gtrx7]

gonna check tomorrow to make sure i still got spark, even more random i noticed after trying to crank it for a while before that when all my aux lights are on after a few cranks the oil one goes out and even when i turn the keys off or remove them then try again it doesnt come back on , only if i leave it for a good 30 seconds or more does it reappear. just really dont know where to start , as i say it was fine until this :S

[teflon_jones]

Fuel, spark and air are where you start. Try cranking it over, then pull a sparkplug and see if it's wet with fuel to verify fuel is ok. Air shouldn't be an issue. For spark, pull each wire off the sparkplugs and leave a tiny gap while you crank it and see if you see a spark jumping the gap.

[gtrx7]

its the fuel pump or related.disconnected the fuel lines to the engine turned the key nothing came through and cranked it over and still nothing , car has plenty fuel in so guessing wiring for the fuel pump,

next question is where do i start to diagnose what the fault is ?
where is the fuse/relay for this ?

thanks for the help thus far

[gtrx7]

ok no updates as such but more trial and error.
ive removed the turbo timer just incase it was that (was on a proper harness) so no problem.

Checked the connector plug on the fuel pump and it had power
(no sound of the pump priming etc so went and bought another fuel pump)
plugged it in and exactly the same problem
(checked the old pump with direct power from a battery and it worked)

so to clarify.

theirs power going to the connector plug that goes on the pump.
the pump isnt pumping or making any noise priming.
i have spark.
i have checked all the obvious connectors and all seem fine

anyone else got any ideas ? as im stumped now.