I've ran em on 4 Toyota's now (3 pickups and my current 4Runner) without ever having a problem. Don't buy the universal model...buy the OEM one and it'll match the factory.

And if you've never seen them that cheap, look here:

http://www.autozone.com/N,16100117/s...eResultSet.htm

Again this is for the 1st Gen 4runners and the pre-1989 pickups.

 

I would also check your coolant temp sensor (on the right just below the throttle body)

if it's not working properly, your engine will think it's cold all the time and run rich accordingly. more fuel use , plus less power = lead foot.

plus they're cheap, schuck's has them for $15.

 

Wouldn't all these sensor trigger the CEL is they went bad? My understanding is that they cross reference their results and ignore the odd man out so to speak. I'm not expert here though.