Originally Posted by
Z U L8R
dirty mech knows whassup.
there's a technical service bulletin aka TSB (information the car manufacturer releases when a certain problem happens to a couple people with the same thing being the culprit)
there's a TSB about the "front engine" wiring harness aka the engine harness that goes to all the sensors on your motor then through the firewall to your ecu
the tsb talks about the wiring harness and having bad connections especially to the injectors. basically inbetween the firewall and the intake manifold (on the passenger side), a little before the harness branches out and goes to all 4 injectors, it corrodes, or gets brittle, or makes bad connections where the 12volt power supply to all 4 injectors, starts off 1 wire, then has the little metal crimp connection and has the 3 or 4 other wires crimped to it right there to distribute the 12v to each injector.
basically here's an easy thing you can do.
get a regular plain jane test light or a low voltage circuit safe test light.
start your car, unplug the injector plug from the cylinder that's misfiring at the time, whether it be cylinder 2 or 3.
take your test light and connect it to a ground or the negative on the battery. probe the 2 pins on the injector plug. if neither of the pins make your test light light up then you know the injector's not getting any power, try wiggling the wiring harness and see if it lights up. find your bad connection and repair. if your test light lights up and it stays lit when you jiggle the harness in different places then getting power to the injector is not your problem and continue to step 2
now take your test light and connect it to the POSITIVE terminal on the battery because now we're searching for a ground.
probe the other wire on the injector plug and your test light should flicker. this is called "noid" signal. the ecu gets it's reference from the cam angle sensor that's built into your distributor and knows when to send these ground pulses to each injector thus making the car run. if your test light is not flickering, try wiggling the engine harness in different places and see if you can get it to flicker, if it does then repair the connection in the harness. if it still refuses to flicker then look up a KA ecu pinout and identify your injector #3 or #2 (whichever one's not working at this time) signal pin. with your test light still on the positive, poke through the injector #3/#2 wire and see if you're getting a ground pulse at the ecu. if you are then your ecu is good, and somewhere from the ecu to the injector plug the wire is broken. you can run your own wire from the ecu to the injector plug (the "shadetree" way) or you can probe that signal wire going further down the harness closer to the injector plug and when you get to a section where before you had ground pulse, and now you don't, then you know your problem is in between those 2 points. repair harness.
if your test light doesn't flicker when you probe the injector signal wire at the ecu then either your ecu plug is not in all the way/jacked up/cocked to the side, or you have a bad ecu, try known good ecu and continue.
you should come out to roswell and lemme fix it ^_^
gl,
Dave =]
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