i have no pulse to the #3 injector but have pulse to the rest of the injectors. what could be the problem?

 

possible bad injector driver in ECU, wiring issue, etc.

How do you know that you are not getting pulse?
Did you use multimeter, noid lights or what?

Need a little more info please...

 

i used a noid light

 

have you checked to see if you are getting voltage at injector?

 

no im going to check it out more in the morning its late and cold. just wanted to get some input on what i figured out so far.

 

Pardon me if you already know this, but the injectors should see 12 volts all the time. The ECU completes the circuit to ground.

If the wiring has continuity to the ECU, I would suspect the ECU itself as the cause.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Perfectionist &raquo;</TD></TR><TR><TD CLASS="quote">Pardon me if you already know this, but the injectors should see 12 volts all the time. The ECU completes the circuit to ground.</TD></TR></TABLE>This is true. But here's some more explanation...

If the injector is NOT getting +12v from the main relay, the noid light wont light up, even if the ECU is fine. You need to check this with a voltmeter, not a noid light.

If the injector IS getting +12v, then the voltmeter can show this. If so, and the noid light doesn't light, then the ground side of the circuit is the problem. Either the wire going back to the ECU is broken, or the ECU is bad. You can check this by jumpering it to ground back at the ECU, checking for continuity to ground with a multi-meter.

 

Thanks JimBlake, seems you knew exactly where I was heading with diagnosis on this one!!

 

i have continuity. im going to check for voltage?

 

voltage is not reading at all in #3 injector plug and is real weak in all the others.

 

I don't remember which wire is which, but it doesn't help to measure voltage across the 2 wires in the plug. One wire needs to have +12v when you measure from that wire TO GROUND. That comes from the main relay, whenever the key is turned on. First check if this part is OK.

The other wire in each connector goes back to the ECU. This should be open-circuit to ground most of the time, but the ECU will close that circuit to ground only during the moment it wants the injector to fire. Get it? The noid light will blink during the moment when the circuit is completed.

You have one injector that doesn't fire the noid light. You need to figure out what's missing. Is it missing the constant +12v from the main relay; or is it missing the momentary ground connection from the ECU?

 

thanx for all the help, comes to find one of the wires going to the resister box was broken at the pin. fixed it and every thing is good. thanx agian for the help and support honda tech is the ****.