B16Civic93

Ok so heres a quick rundown of the car.

1993 civic ex coupe

LS/Vtec Turbo. tuned with neptune on a p28.


Car wouldn't start, checked it out it has spark and gas, main relay is good, fuel pump is priming and good fuel pressure(gauge). Unplugged one of the injectors and plugged in a noid light. While cranking the noid light doesnt flash. Injectors aren't getting a signal.
Replaced the distributor with a brand new one. (CPS) still nothing. I removed the injector clips and checked for continuity between the injector plugs and the ecu plug, all good. I have 12 volts at the injectors on one side. The car will start and run every once in a while and when it does the injectors are pulsing(obviously). If I shut the car off and come out the next day it will not run. I also checked and I have power at the IGP1 and IGP2 pins on the ecu.


I am stumped. Someone PLEASE HELP!!!!!

Runnerdown

Sounds like you have ecu problems. That will ground the injector (pulse) and you already stated your constant 12v supply is there.

fcm

Ditto the above, sounds like a bad ECU/ECM, can you get another one to try?

Just because, redo the main grounds, [batt. to chassis/chassis to engine/thermostat grounds] anytime you have an electrical issue the grounds should be redone to eliminate them as the possible problem, [DO NOT just eyeball them, or check if they are tight] disconnect/clean/reconnect and pay close attention to the thermostat grounds. 94

B16Civic93

Yea bad ecu is what i'm thinking too. I was hoping there was something else that I was forgetting to check or missing. I removed and cleaned the grounds... well most of them lol. I even added a ground from the thermostat housing to the valve cover to make sure that was grounding correctly. The battery is relocated to the trunk and I didnt take apart and clean the battery connection and where I have it grounded to the chassis. Hopefully that's the problem. It's just weird cuz it will start and run sometimes. I figured if it was the ecu it would do it all the time. I guess I can open the ecu and see if anything is burned up.

B16Civic93

So I removed and cleaned every single ground. Checked for ground at the ecu pinouts that require ground. Checked for continuity between the 3 sensors in the distributor and the ecu plug and thats good. I've literally tried everything that I can think of. My tuner is going to send me a new chip for the ecu and see if that fixes it. Oh and I also removed the back of the ecu and checked for any burnt connections/soldier joints.. Anyone else have any suggestions?

motoxxxman

what is the resistance of the injectors themselves?
are you using a resistor box, or have any resistors wired into the injector wiring? if so, where?

fcm

It sounds like you have eliminated grounds as the problem, now check for required powers, don't forget to test for power with ign. switch in both the run AND start positions. 94