2wd Cosworth running L8 ecu with wasted spark board. Brand new engine loom.

I put the car on the road last year and every now and then it would just cut out and not run. The car would start again after a couple of times cranking it over and run fine again for weeks.

I fitted a new battery the Friday before National day as the old one was knackered. The car ran without fault on the friday, really smooth with no miss fires, didnt cut out etc.

I came to the car on the Saturday morning and it just wouldnt start. I tried all the connections and still nothing, would just turn over and not fire. I swapped some bits off my 3dr that i knew worked like the Phase sensor, CPS and still nothing.

I then tried it and it fired and ran for about 5 seconds, then again for 15 seconds the next time, I fired it up again and ran for a minute + as it started to die i got under the back and the fuel pump was making a puffing noise. The next time i fired the car it started and idled fine and then was fine every time i turned it off and on again.

I went and drove the car but it now had a very faint missfire on constant Throttle, fine at WOT and acclerating upto the point of constant throttle at say 3000rpm, would idle fine aswell. I turned it off at a mates then as i drove home it was fine back to how it was the day before. I stopped on the way home switched it off and had a look around it, then as i drove the last bit home it was missing again. Then the car wouldnt start again the following morning and i havnt touched it since really.

I sent the loom off to get checked and that was fine. I have a new set of Ign amps to fit, fitted a new PF09. I have a new coil pack, phase sensor, map sensor, cps all to try if she wont run.

All the parts and sensors were new when i put the car together last year, Fuel pumps and fans were rewired aswell. Fuel pump was a brand new 044 i had done about 6000miles on.

I am just wondering if anyone has any ideas on what the fault could be?

I have posted it in here as it gets more views than the tech section.