STI581

Hey guy's i have a really wierd issue..first off i did some research on here and can't seem to find the correct answer. well it starts off like this, i bought the car and it was in a non running condition. I found out that someone who didnt like the previous owner descided to cut wires under the engine bay. wires that were spliced were as follows :
distribuitor
fan
abs unit
relays
abs relays
harness bundle next to fuses
harness close to drivers side hinge under the hood.

Well long story short i rewired every wire by solder connection and heat shrink. I then went in the car tried to start it up and walla it fired right up except i got a pretty rough running car. so then i began my diagnosis and thought it was a fauly distributor well eeeeeeeeeeeg nope replaced it and same thing. all the wires have spark and every injector is spraying except for possibly cylinder # 4, then i assumed hey bad injector well nope did a swap with # 3 and same thing...but when you unplug everyone you get engine bog. But when you unplug # 4 you get no decrease or increase in roughness...so my guess that its cylinder #4 wiring....what do you guys think? is there a wiring diagram that could help me out that some one knows...or where the injector wire loom goes to? I also forgot to mention i tried the spark plugs and they all spark as well as cut engine power except for #4 but i do have spark there..so its definatly a fuel problem...please help me out!!!

Thanks,
A

Fuse

Get what is called a noid light it is used to check the injector on off signal. If it will not blink you have a wire problem. http://www.etoolcart.com/browseprodu...t-AST7898.html If you want a diagram go to www.hondatech.info and do a search on your car. Injectors wiring is very easy the hots all tap into the main relay and the grounds are controlled by the ecm. So you can also test with volts one wire to the injector should have 12 or some times 5 volts. If you have a digital multimeter you can test the ground with hertz, duty cycle, rpm what ever.

Don't forget you need fuel,spark and COMPRESSION to fire a cylinder.

STI581

I know the essentials for what you need in order to have the 4 strokes to process throughly. The only wierd thing is that I took an ohm meter to the injector plug and it did not signal back and fourth while the car is running it stayed at 1.0 to 1.1 ohms but the other wire was around 1.7 to 2.0 back and fourth when it is given a signal to fire the injector. I noticed this on my digital ohm meter...I am wondering if the relay for the injector is where my problem is...because the 1.0 means its getting power and is grounded suffeiently....but the signal portion of it from the relay sounds like its not working properly and thats where i bet my wiring job came into play as it may have not wired properly.....who knows but sort of catch my drift??? or am i on the wrong path...

JimBlake

Ohm-meter isn't the right tool for that. You can use a multi-meter to check a few things...

Unplug the injectors. One wire on each injector should have battery voltage whenever the car is switched on. (The ECU closes the ground side of the circuit to fire each injector.)

The other wire on each injector goes to it's individual pin on the ECU. I don't have a pin-out drawing for 1996...

When running, most multimeters don't update fast enough to see the pulsing. That's where a noid light is useful.

STI581

ok i have a wiring diagram for this car...here's where this gets really funny...I took my multimeter and measured for voltage for the red/blk wire according to the honda service manual and found out that it does see the battery voltage for that specific cylinder #4 as well as #3 which i use for comparison since i know #3 works fine. Now i guess the test comes to the ECM..I'll do that tomorrow night where i will check for voltage to the A2 pinout with A23 as the manual says to....but what about the injector resistance box...do those usually go bad? if so how can i tell...i highly doubt it...but the manual says if i dont see voltage on A2 then i have serious issues with the ECM....which i highly doubt that....this is a really crappy ,mess here

STI581

anyone with ideas?

Fuse

See if you have power to the resister box if you do and you have no power out of it you have a bad resister box. I have seen one or 2 fail. You can ohm out the negative wire from the injector to the ecm have them both unplugged you should have 0 ohms. Also check and see if the wire is shorted to ground when you have it unplugged.


I thinks it the power problem is causing the bad running engine fix that first and see. The only way you can see the ecm turning off and on the injectors is with a noid light, or a meter that has hurts function or duty cycle. To use hertz tap into the ground wire with everything running and plugged in you should have hertz or duty cycle. You can use rpm on the meter too but it gets strange you should see rpm.

I talk in order so don't jump around about what I say or it will gets all mest up.

STI581

i figured it out!!!! when i reran wiring and soldered wires because of the mess the car was in the first place..i remeber that i soldered two yellow wires by the resitstor box. I traced the negative wire from the ecm and no power at all..well strange enough i rewired the two wires yellow to be exact for injector # 4 and sure as shit it was crossed on accident since i didnt know which wire went to which ha im so glad its over!!!!!!!!!! Fuse you sound like an electrical guru? thats awsome man well i wouldnt give up so im glad i did it!

Thanks for the help gentelmen!!!