In that case, you can test the TPS with a cheap multi meter and a haynes manual. You can test all the other sensors too with those items . If they all check out, then move on to compression tests as others have stated .

 

Maybe bad O2's, no cat, possible bad TPS..shouldn't the CEL have exploded by now? Should jump all over that comp test, the blue smoke could be piston related not just valves. When looking in the IM was the TB removed?

 

I definitely have had the cel on numerous times a po420 only, would come and go. I cleared the code after I was done working on it. And the tb wasn't off when I looked in the IM. That would be another thing to do take the tb off and have a look??

 

yeah it ill give a much better visual to what's going on..scoop up a new TB gasket before hand tho..P0420 before the cat removal make sence. I think a TPS w/low or high voltage should show a P0122/P0123..All the guys on here who know what they're talking about always tell me not to just throw parts at it..make sence unless you're loaded..(don't mean drunk)

 

FYI I never set a CEL when my TPS was faulty.

 

still sportin the original TPS (98' 267k) ;D *knock on wood*

 

Well I got a new tps put in and have not had an idle problem since ... Haven't had the time to do a compression test yet but I'll be doing that soon .. Thanks to everyone for all the help I'll give an update after I get my compression numbers