ihc300zxt.t.

I have a 1991 300zx tt , just got done upgrading the fuel injectors .. when I went to start it the fuel pump came on and shut off... it did this a few times ...I was wondering if anyone had any ideas

nismo619

too much fuel pressure ? try to take off your gas cap..if the pressure is ad normal then u will have to upgrade your ecu to accpet your new fuel injectors

ihc300zxt.t.

I already upgrded the ecu from jim wolf technology ...... list of some upgrades 550 turbos , jim wolf twin pop charger , rods and pistons , blitz boost controller , apexi super air flow converter , blitz turbo timer , nismo injectors

ihc300zxt.t.

the pump doesn't turn right on when the key turns.....it will come on for alittle bit the shut off ( like it looses power ) I have a fuel regulator on the fuel line... it climbs to about 45 psi and drops

jfairladyz

When you turn the key on shouldn't the pump only turn on long enough to prime the fuel system unless you start the car? I could be wrong

ihc300zxt.t.

ok checked tto see if it was priming when the ignition is on .... it not doin anything now ... could it be the relay???????

CanyonCarver

Start with a new relay and clean all of the electrical connections in the fuel pump circuit. If that doesn't fix it, maybe try running some wires straight from the battery to the pump to see if the pump still turns off in the same manner. If the pump runs fine that way, there's a chance the fuel pump controller is bad. I dunno how to check it without swapping in a known good one.

ihc300zxt.t.

ok I have fuel pressure now but still won't start. I replaced the plugs but noticed the security light flasing,,,would this have anything to do with it????????