drpdmazda

hello everyone, i recently picked up an 87 4x4 x-cab pickup and have a question regarding the O2 sensor. the sensor i have a question about is the one closest to the header in the downpipe. the truck i bought has an O2 sensor there but it isnt plugged in to anything? it has a rubber boot on the end of it that really looks like a boot that would go through the firewall. I cant find anywhere on the firewall that it would have come out of and i cant find a plug that it is supposed to mate with. it has a yellow 4 prong plug on the end of it but i cant seem to figure out where it plugs in at. any help would be greatly appreciated, i can get pics of what i am talking about if it will help. also i was wondering if someone can tell me how to read the codes to see why my check engine light comes on and off periodically. the guy had the head off and when he put it back on he didnt hook up the vacuum lines properly so they were a little out of whack for a short time, they are all fixed now and i did a fresh tune up and fluid change to the truck so i just need to figure out the O2 issue and the engine light and it will be good as new again. forgot to mention it is the 22re motor


thanks

-jason-

83

You don't have a first gen pickup

drpdmazda

your right +1 for you, sorry about that my second gen pickup

4Crawler

iTrader: (3)

How to read check engine light codes:
- http://www.4crawler.com/4x4/CheapTri...CheckConnector

There should be a plug for the O2 sensor someplace low on that side of the engine. And I think there is only one sensor on that vintage 22RE, don't think the post-cat sensors started until the '90s model 50-state smog engines.

drpdmazda

thanks for that link, i used to have that saved in my favorites until my computer crashed. i havent had time to get under the truck and look for the plug yet but will update as soon as i do

drpdmazda

there is indeed only one O2 sensor that is in the manifold but it does not fit the plug that you have pictured. i have that yellow plug on my inner fender near the master cylinder but the plug on the sensor does not fit that one. the plug you have shown is black and the plug on my sensor is yellow? i am going to get a new sensor on wednesday to replace this one and see if maybe the previous owner had the wrong sensor and that is why its not plugged in.