I'm not near my truck, so I can't go look.

My GM truck has 2 upstream and 2 downstream O2 sensors, for a total of four.

How many are on the 4runner, and where are they located (upstream, downstream, etc)?

THX!

 

i dont have a 2nd gen so i cant be sure, but im pretty sure i just read yesterday on here that you have one, upstream of your cat. and thats it

 

I only have 1 before the cat...91 4Runner 3.0L

I *THINK* only the OBDII ('96+) engines have 2 O2 sensors

 

yup just 1 in front of cat

 

California trucks have 2, one in front, one in back

 

mine 91 only had 1

 

Yeah my 93 only had one. Just get under the truck and look, it's not like they are hard to see or something.

 

wrong, depends on the year.

 

Thanks for the feedback guys. Mr goat, I have been under the truck this morning and confirmed only one.

I asked yesterday because i needed to know, and was 26 miles away from the truck.

Thanks for reading and replying.

DCS OUT!

 

Fair enough, my FSM only works for one year. I suppose if you go back far enough, there weren't any O2 sensors