o.k I finally found the 02 sensor and there are 3 wires on the same harness going to it,2 are connected to the sensor and one is just hanging there,I dont see where it could go.Anyone know where that plug (wire) is supposed to plug into?? it looks important,maybe its whats causing the surging problem?

 

The O2 sensor on a BII is either a 3 or a 4 wire sensor (can't remember for sure, I want to say 3). A 3 wire sensor has one wire for the O2 sensor signal to the PCM, one wire that feeds power through the ignition to a heater in the sensor, and the third wire is a ground to complete the heater circuit. Having one of those wires not plugged in could cause problems, do you get an O2 sensor code from the self-tests? Can you identify which wire isn't connected (may need a wiring diagram to look it up)?

 

2 wires are like part of the 02 sensor this one has a plug end to it like it should plug into something.. its on the same harness tube this is an 86 b2 I don't know how to run codes yet,I'm nowhere near your talent level ...poverty is my main motivator in doing this work..although I do love this truck and I'm learning a ton from this site thanks to you and your friends here

 

i love this website there's so much helpful sources and intelligent people that are registered on here, its great, i need to check out my O2 sensor, by the way if i gutted my cat would i need a new o2 sensor or anything? everyone on here said gutting it would hurt performance but i totally disagree on that one, not only has it helped performance but it sounds soo much better, i have people come up to me asking what i have under the hood and i show them and they're like d@mn i like that sound, but what should i do in the case of the O2 sensor? thanks

 

dogg16: Running codes is easy. You'll need a jumper wire (paper clip works) and an anaolog voltmeter or testlight. Follow the instructions laid out by our moderator in the technical information post at the top of the BII forum.
I think I'm a little confused. How many wires coming out of the O2 sensor itself? Just 2?

RomerB2: You shouldn't need to make any adjustments to the O2 sensor just because you gutted the cat. Run the self-tests to see if the computer can see a fault with the O2 sensor. If not, then "if it ain't broke, don't fix it."
The usual performance "loss" when gutting the cat is a loss of low end torque. Truck engines, as opposed to car or race engines, are usually tuned to deliver a smooth torque curve over much of the RPM range, with an emphasis on low end torque for heavy pulling at the expense of high end horsepower. Most engine performance modifications work by shifting the torque curve higher in the RPM band which does increase horsepower, but you lose some low end. If you're happy with the results you get, then I'm not going to disabuse you.
However, I do feel an obligation to point at that, unless you live in a country that doesn't care, It's against federal law in the US (and Canada, too, I believe) to remove or disable any emissions device. Granted if you live somewhere in the US without an emissions testing program, your chances of getting caught are slim to none.

 

Mr.Shorty..yes there are two wires coming from it,the chilton book shows a pic of it and that also has two wires..its the third wire in the skin that I am concerned with,it has a plug end and its not connected.......just to verify I'm lookin at the right part,its located just below the exhaust manifold and screws into the block right?also the wires are blk/wht-ylw/org and the loose one is grn/blk

 

Att: Mr.Shorty..I am embarassed..that is not the 02 sensor..I found the 02 sensor on the exhaust pipe junction I am sorry for wasting your time there I think thats the knock sensor I was looking at..I'd still like to know what the loose wire is

 

here in oklahoma we have no sniffer test at all, no car inspection or anything, i can drive by a cop and he just waves, it's not a deal at all here, i thought it increased my low-end torque, or at least it feels like it, and that also may be because i had a clogged cat therefor limiting the torque anyways, so i think that it's helped, im fixing to do the 85-86 TB and CAI which i think will help, thanks for the feedback