Z99doc

i had to replace the engine and harness in my 92 Honda Prelude. finally after so much hard work i got to turn the key annnnnnnnnnd nothing..... so i do it again and again and again and nothing happens other than the engine cranking. then we used a node light to see if the injectors were getting power and no power to the injectors. if anyone can help it would be highly appreciated.

98vtec

did you put the ground back on at the thermostat? without that ground, nothing will work.

Z99doc

Yes. my father even took it off cleaned it and then put it back on.

98vtec

does the fuel pump prime? check engine light come on then go off after priming?

with the ignition on, injector unplugged, both sides of the connector should have 12v.

the yellow/black wire goes to a power/ground distribution block that is found on the back side of the engine in the engine harness. its the only big connector with a dead plug in it. the injector wires are fed to that. If the cap is not on that plug, power cannot be distributed so if you dont have power to the yellow black wire on the injector, make sure the cap is there first. there should be a single yellow/black wire coming into that plug and it comes from the main relay which is energized by the ignition switch. so make sure you have power going to the power distribution plug. If you have power going in, but not coming out, you have pinpointed your first and maybe THE problem. But if you have power on the yellow/black wire...move to the next step

the colored wires at the injectors (blue, red...etc) go straight to the ecu and are only grounded by the ecu when it gets the signal to ground from the cam/crank position sensors but will have power until grounded. I dont believe it matters if the injectors are plugged in or not for that test. just easier to probe the terminal with it unplugged.

If you have nothing coming from the ecu, make sure the ecu has power which will also be a yellow/black wire. Pin 25 on connector A is the power source:
http://technet.ff-squad.com/wiring.obd1.htm
that power source comes from the main relay. If you dont have power going to the ecu, you will need to test your main relay and be sure its receiving power from the ignition switch.



Do you have spark? why did you replace the harness to begin with?

Z99doc

Yes im getting fuel and I am in the middle of a swap it went from auto to manual. This is my first swap and believe me I have asked a ton of dumb questions on this site. I will try doing what you said to do tomorrow I really appreciate the help thank you. Please keep the ideas coming.

minilogoguy18

Should be able to figure it out from there, the service manuals may be floating around the net but you guys are missing the ETM's that are just as important. Circuit is super simple.