Just finishing my build. I don't get much time to work on the car so this project has taken forever to get done. Everything is buttoned up now, the motor spins, gets fuel and oil pressure, but won't fire. I'm thinking it has to be something with the ignition. I didn't change any of that during the build so I'm not sure why it isn't firing now. Plugs were still good when I took them out, but I'm not sure how to go about checking the wires or the coil packs. I did check the fuses for even and odd coil packs and they are fine. Any ideas on where to go next? Crank position sensor maybe?
Reloaded the tune and it now fires up, but immediately dies after 2 or 3 seconds of idle. So, I have spark, fuel pressure and oil pressure, but the car still dies. I'm a little stumped here now.
No CELs and the battery has been on a tender for the entire build so the voltage is good. I did do a full write on HPtuners. It did fire up today for several seconds and then died out again, but I did get a log of it to send to RC so hopefully there are some clues in there because I'm at a loss.
Sounds like fuel pump. You turn it on and the fuel pump primes, then shuts off. Engine starts and used up the prime and pump doesn't kick back on. Check the ground under the fuse box near the RT headlamp. Or the pump relay is just bad.
Turned out to be all in the tune. Went three or four rounds back and forth with Rick and he figured it out. Engine runs just fine now. Planning on finishing this build in the next week or so just in time for some of the race events up here. Still need to figure out how to permanently mount the enormous intercooler that I have. It'll take some fabrication to get the steel bumper to squeeze back on.
Thanks for all the feedback on this. I was really stumped as to what it could have been.
Turned out to be all in the tune. Went three or four rounds back and forth with Rick and he figured it out. Engine runs just fine now. Planning on finishing this build in the next week or so just in time for some of the race events up here. Still need to figure out how to permanently mount the enormous intercooler that I have. It'll take some fabrication to get the steel bumper to squeeze back on.
Thanks for all the feedback on this. I was really stumped as to what it could have been.
I think it had much more to do with fuel. I switched to E85 so I don't think I was getting enough flow to keep it running. Spark was there the whole time, but the symptoms seemed to point to spark not being there. This is the first engine swap and blower that I've done myself so it's been a hell of a learning experience. I completely changed the car around for this one.
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