ok, if you're a glutton for punishment, ill post some more.leakyfaucet said:Ahh! No! You're the best chance I've got! Okay, the last thing I did was put the positive prong on my voltmeter into the back side of the left oxygen sensor wire going directly into the female end of the main harness that plugs into the computer (basically I tapped directly into what the computer would see), and I put the left prong from the voltmeter on the ground right next to the computer.
That make sense? That's all I did. While I was there, since I got no voltage, I flipped the switch to display resistance, and got 30 ohms.
So now that you're back with me, should I test the oxygen sensor directly? Would that even work?
BTW, Joe and Giddyup are your best chances at figuring this out, not I. that does not stop me from trying though.
i am familiar with the principles of an EGO and HEGO but not conversant with wire colors, so i wont address any of that (whew!). your post is very articulate and i totally get what you did (the way i read what you did, is called backprobing). that is the way to do it, and i think Joe mentioned something to the same effect. right on.
ok, so no volts. are you real sure you had the right wires? confusion could come from testing at the sensor (as the heating element wires are present there), but with you testing at the puter, it should be a no brainer - im sure you got it right on! (im thinking aloud, since my thinking is so poor tonight - this allows you to follow along and spot the flaws i make).
the sensor need to be at around 500*F, as i recall, to 'light off'. assuming this is true (should take a minute or two (or less), if the HEGO's are working - the HEGO ground is sometimes not attached at the back of the motor). otherwise, light off can take longer (which is why i mention all that).
what i might do at this point (see if others think this is a decent idea): since you got no juice at the puter, go to the sensors themselves and check volts and/or resistance (i think J and G will have ideas for you on how to best do this). if you show something at the sensor and not at the puter, that suggests an open in the wire (i think). BTW, i think the ground for the EGO is in the injector harness - ask Joe to be sure.
that is about all i can think of, and all i dare say at once! i take pride in trying to be somewhat articulate and precise, but not so on this thread - sorry to have made a mess of the thread. good luck with it!