I have 167k on my 4runner and thinking about swapping out the o2 sensor. I don't really have any issues with it, but wonder if it deteriorates over time.
I'm also going to replace my fuel filter. I just checked my tire pressure and it's at 32psi. I replaced my air filter over the weekend, but thinking of K&N CAI, later. Any inputs? suggestions to get back to 20mpg ish?

 

How long has it been since the cap and rotor and plugs/wires have been replaced? Car and rotor would help the engine run a little better. You may want to check your cat. after that many miles, all of mine have been clogged by then, may want to go ahead and replace it (I have a Car Sound one for sale if you want it, 2.25" ID inlet/outlet).

Replacing the 02 sensor would definitely be the first thing I would do...I had 125k on mine and it was bad and the CEL didn't go off and the mileage was crappy.

Definitely do the 02 sensor first and then the tune-up stuff, fuel filter is also a really good idea.

Fink

 

I'd skip the K&N cai and just get the drop in filter. You gain no horsepower and simply lighten the weight of your wallet. For the 200 or so bucks that equals around 8 tanks of gas depending on where you live. Also not to jack the thread but how much are you looking for the cat 4x4fink. I may be interested.

 

Since you're in Cananda I have no idea what the shipping would be like but I'll sell the cat for like $35.

Fink

 

Check your timing too. I haven't used it, but some people on here claim that Seafoam (do a search) really helps.

 

What cap and rotor?

 

I have a 3rd gen w/ a little less than 100k. I just recently did a full service (plugs, fuel filter, oil change, diff fluid swap, radiator flush, tranny flush, BG flush, etc.) hoping to improve mpg. Service didn't do much but the truck runs really well.

There's another thread where an 02 sensor change dramatically increased mpg but that was after a CEL code. Since I didn't have a code, I asked whether changing one would help, as most 02 sensors get "lazy" in time. Most that changed their 02 sensor w/o a code did not get an increase in mpg. Therefore, I didn't change mine. If you don't have the fancy setup, an 02 sensor is less than a $100. If you have one of those air/fuel thingies, those can be pricey. Good luck.

 

at 60k miles..
Only offroading that I do is on snow (boarding)
I'll look into everything and start replacing stuff.

 

I've put some seafoam on the gas tank and oil. My idle was instantly better. gotta clean out the intake system as well.