My son's '97 V6 4Runner is running very sluggish.

Here's what we have done to try and fix the problem: new plugs, new cables, new front O2 sensor, new cat, clean MAF and throttle, reset computer, and a new fuel filter.

Any and all suggestions are appreciated.

 

when was the tbelt last done? Ive seen something fall into the timing cover and make the belt skip causing the timing to be way off. Also, what plugs and wires did you use? Denso or nkg I hope. What does your air filter look like?

 

yes i would also check for drive belts for slippage. Give it the seafoam treatment, and possibly run a compression check to see the health of the engine.

 

Had the timing belt changed out 2 yrs ago, less than 20k miles on the new one. NKG I believe, but it was running great after I changed those. Approx 1.5 years ago.

I changed the first sensor in front of the cat. I think I replaced it with an O2 sensor. Just read that one is an a/f sensor. Is that correct?

 

Not on a 97. They didnt start to change the #1 sensor to a/f sensors till 99. I would recommend having someone look at it. You will be time and money ahead instead of replacing every part you can hoping to fix it