Hey guys, I have an EF xr8 that wont keep running. I purchased it off a friend on the weekend that had lost interest in it and has been sitting for 18 months but was running fine when parked. there has been a lot of money spent on the motor including: full rebuild, gt40p heads, upgraded valve springs, crane Cams mild cam (not sure on specs) and crane cams roller rockers. The car is also running a stage 2 J3 chip and the car has done about 1000k's after all work was done.

Now once i got it home off the car trailer I sucked all stale fuel out of the fuel tank and replaced the fuel pump, in-line fuel filter, blew out all fuel lines, cleaned all spark plugs and dizzy cap contacts, checked all vacuum lines and intake connections.

When i crank it over it starts and runs for about 2 seconds and shuts off, initially i thought maybe the fuel pump isn't running continuously after startup and shutting off so i tested that with a test harness and multimeter but it all tests out good. So I checked the Fuel pump relay and ecu relay connections and even swapped relays with another spare I had, still no good. Next thought was the J3 chip, So I unplugged that and tested it, still no good.

I wasn't convinced so I played around with the J3 chip for hours and eventually it was running, but once i got it running it was missing and backfiring like crazy. I checked all spark plugs for spark and they were all okay. I couldn't figure out why it was missing so I went inside and had lunch. Once I came back outside after and hour I tried to start it and it wouldn't bloody start again!

So I played around with the J3 chip again and no matter what I do I cannot get it to run for longer than 2 seconds. I am stuck on where to go next because it seems very electrical like the power is getting cut to the injectors maybe? any help or thoughts from anyone would be awesome.

cheers

So I haven’t been able to test fuel pressure yet as I don’t have a gauge but I have found one strange thing about it.

I can start the car and rev it to 1500-2000rpm and if I hold it there or higher it will run but once I let the revs drop below 1500rpm it dies.

Since my last post I have replaced every vacuum line with brand new stuff, installed new tfi module, cleaned distributer points and spark plugs, checked all engine loom wiring, installed another isc off another spare intake I had as well as remove fuel rail and injectors and flush and clean all fuel lines and clean intake and bought new J3 chip.

The fact that I can also run it off aerostart when idling symbols to me that it is cutting fuel supply or not getting enough fuel supply but how come once I rev it up at 2000rpm it runs fine? Hurting my brain at this stage

Just an update to my last post

So I finally got around to buying a pressure gauge, I hooked it up to the valve on the fuel rail and cycled the key. 40 psi on first cycle, on second cycle it went to 65 psi but slowly dropped back down to 40 after a little bit, the book states 275kpa (39 psi). When running it is sitting at 75 psi and is steady, which is 510 kpa. Book states when idling minimum is 275kpa. To me this sounds all healthy, what do you guys think?

Cheers