j30

[allnabbott]

son bought a 93? j30 and it has a miss on the back left cyclinder(as you sit in driver seat). injectors check out ok but connector on injector is not showing current. how can i(if possible)go around this. can i go from ecu to connector with new wire. all others are firing.

[swimshark]

http://www.twinturbo.net/nissan/300zx/f ... p-plz.html

[allnabbott]

great info. my problem seems to be no signal to injector. plug in test flasher to test circuit and this was the only injector not receiving signal, that's why i wanted to know if i could go from ecu to plug with new wire or is there a block or something in-between ecu and injector. no mechanic by any means but have played with engines all my life. just getting too complicated for me now.

[fourdrinie]

sounds like the power transistor unit is the culprit...or one of the wires going from the ECU to PTU and then onto coils....I would replace the ptu first, or check the wiring from ptu to coil and ptu to ecu for a break....

[fourdrinie]

or at the very least, remove the ptu and clean the contacts!!!

[allnabbott]

thanks, will try.

[allnabbott]

i have tried everything reccommended and i still am not receiving a signal at the injector. could the problem be with the ecu not signaling the number 6 cylinder injector. have proper voltage and resistance with everything and have cleaned contacts on ptu. still have miss.

[fourdrinie]

Have you tried disconnecting the battery, then disconnecting ecu, cleaning contacts, reattach making sure connection is secure?

[allnabbott]

i have disconnected it several times. checked continuity from ecu to injector. everything is checking out but can't get rid of miss. pulled ptu and cleaned contacts on that to as you suggested. i'm at a loss but want this thing fixed so my son can drive it but more-so that i can get it out of my garage.

[allnabbott]

am i not correct in my thinking that the ptu controls the fire to the plug coil and the computer controls the injector signal?

[fourdrinie]

if you read the FSM, EC-290, the injector is directly wired to the ignition switch, the ECU provides the ground, not power...test with the ignition on, pin 2, right hand side with the notch up, should be 12v. Then test if youre getting ground to the ECU....

[allnabbott]

just to let you know, finally solved mystery, was ecu.

[fourdrinie]

Glad you got it solved!