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Jdm swapped fc w/ starting problem

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Old 05-10-11, 12:26 PM
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Jdm swapped fc w/ starting problem

i recently just put in a s4 jdm 13T into my fc and before it was s4 n/a im using the jdm harness that came with the engine but i cant figure out why its not starting it has to be an issue with the wiring to the starter because when i do try and start it, it cranks like the battery is bad but ive had the battery checked its good and had the starter checked also and i already wired the alternator in but still cranks slowly i dont know what the problem could be
Old 05-10-11, 04:52 PM
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The fuel lines may be backwards. For J-spec engines, the order is:

Feed line -> Pulsation Damper -> Secondary Rail -> Primary Rail -> FPR -> Return

Originally Posted by 88jdmfc
im using the jdm harness that came with the engine
Did you just plug it in without re-pinning any connectors? Harness junctions FEM-01 and FEM-02 must be rewired if you use a TII EM harness on an NA chassis. Using the existing NA harness is far easier.

https://www.rx7club.com/2nd-gen-archive-72/s4-na-turbo-swap-details-813825/

FEM-01 / 02 wiring: https://www.rx7club.com/showpost.php...92&postcount=9
Old 05-15-11, 09:00 PM
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ya i just plugged them in but i figured that ur right and right now im taking off the jdm harness and using the n/a one and since im doing this im blocking off all emissions and keeping the omp.....but do u know what i have to wire in?
Old 05-15-11, 09:54 PM
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Use the N/A harness.it is alot easier.
The Tps wires need to be lengthened.Make sure you get them right.(the car will be a BITCH if ya don't!)
Old 07-09-11, 05:41 PM
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No fuel in return line in fc

hey i have no fuel in my return line in my new jdm 13b swap im thinking it could be a bad o ring in the fuel supply circuit but i dont know where that is at if thats the problem and the car starts for like 3 seconds and than dies i dont know if that has anything to do with the return line also and i do have the fuel lines hooked up correctly i was aware that the usdm and jdm are different and i have also installed a walbro 255lph fuel pump....I apprecitate the help thnx
Old 07-09-11, 11:12 PM
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Originally Posted by RotaryRocket88
The fuel lines may be backwards. For J-spec engines, the order is:

Feed line -> Pulsation Damper -> Secondary Rail -> Primary Rail -> FPR -> Return

Maybe....?


Old 07-10-11, 08:33 PM
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nope made sure it was right and i even did it the other way just to be sure and it didnt even start up and still didnt have fuel in return
Old 07-10-11, 08:53 PM
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Have you tried to jumper the fuel check connector to see if this helps to keep the engine running for a longer period of time?
Old 07-10-11, 08:57 PM
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ya tried that didnt work that was the first thing i tried
Old 07-10-11, 09:21 PM
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Have you been able to verify the fuel pressure going into the engine or at least tell if you have fuel flowing from the filter? Someone else recently on the other board had a clogged fuel system due to a faulty attempt at repairing the pulsation dampener. You might want to try testing if you have fuel flow after the secondary rail and go from there.
Old 07-10-11, 09:27 PM
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theres definetly fuel coming from the filter cause it will start up just not stay started and i felt the line and felt the fuel flowing and i know theres fuel flow after the secondary also just not in return line but i was also wondering if the primary injectors were clogged could that prevent fuel going through the return line?.....i also did full emisison elimination and blocked off everything except the omp idk if that will give any insight or not
Old 07-10-11, 10:57 PM
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W/the key to on and the jumper in place the fuel should flow through the system and thus out the return line so the injectors don't play a role in this as they would be inactive and not hinder the fuel flow in any way, so the fuel pressure regulator could be the problem here. Is the regulator stock or an aftermarket adjustable variety?
Old 07-11-11, 12:03 PM
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its the stock fpr
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