I have a 93 22re 4runner 5spd and the past 2 weeks i have been getting 70-120 miles less per tank and i have considerably less power then before. Also recently ive noticed that when i let go of the throttle the truck kind of lurches and slows down faster then before ( I thought that this might have had something to do with my airbox mod) but in the last week when i try to go up a hill on the highway that i used to be able to do in 5th gear the runner now bogs right down and starts making a very loud, bass sound kind of like an exhaust leak but it only does it under a load and at lower rpms. Any ideas as to what has happened. No CEL has come on and my 02 sensor, air filter, spark plugs were all changed recently and my tire pressure is ok.

 

Your catalytic converter is probably melted inside or clogged.

 

I never would of thought of that, and my cat is probably old. But wouldnt this cause my truck to make a gross sound all the time.

 

Not generally.
Clogged cat, problem in the muffler, bad O2 sensor, time for a new air filter, time for a tuneup, time to seafoam, all sorts of things can cause what you describe. But from your description it appears there is something else you should know - use that shift lever more often. The only thing that will quickly kill a 22RE (and most any engine for that matter) is lugging - big throttle loads at low rpms. Downshift for the those hills, it aint' a torque monster. Keep 'er spinnin' and she'll be much happier. Lugging also will shorten the life of the cat by the way.

 

ok i just went outside to look at my cat and i have some news that will probably upset some of you guys, yep i dont have one. The law in Canada i believe is that vehicles 10 years and older dont require a cat. Ive been under there many a time since i owned this vehicle for the past year and i never actually noticed i didnt have a cat. Also i know what your saying about shifting its not that im trying to stay in 5th gear no matter what its just that hills that i used to just coast over in 5th i now have to downshift to 3rd. And this is not something that happened gradually it was fine about 3 weeks ago and now its been horrible for about a week

 

If it feels like a loss in power, might want to do a leakdown/compression test to figure out if the motor is "healthy". This also helps diagnosing...if the motor is ok, then check your ignition, fuel components, maf, etc. Most FSMs have good trouble shooting sections that will point you in the right direction.

 

have you done anything to the truck between the time it ran fine, until it started acting up? the airbox mod causes the intake to have a deeper sound to it, maybe you didnt connect a air hose or vacuum line. what other mods have you done that might help us

 

The only thing i have done is on the airbox there is a tube it breathes through and all i did was take that off. I noticed it did have a throatier sound but thats not the sound that im hearing now.

 

All the tubes are there for a reason and you should be sure that they go in their respective spots. messing with your emisions will cause your ECU to freak out and you can damage you engine in some cases. The engine and all it components were designed to work with the emisions. Start by putting some seafoam through it, could help at the worst you will clean out a lot of carbon buildup.

 

winter gas makes my truck noticbly slower, and lowers my gas milage...it also doesnt help when you're using 4WD more and more

 

I think it just may be a bunch of totally unrelated things. The sound is probably my muffler because it keeps getting louder and louder as the days go by (any way a crappy muffler can do any of the symptoms above). The mileage may be just a combination of bad ignition wires, and colder weather. And "supra" the tube i was talking about isnt a hose or anything its the big pipe that comes out from behind the headlight and goes to the airbox from which the airbox draws air through.

 

Yeah, if the muffler is falling apart internally it can make a pretty big difference.

 

FWIW I had very similar symptoms a couple weeks ago and found one of my spark plug wires was toasted...doesn't hurt to check

 

yeah im definetly going to get new wires tommorow, but i have driven before on 3 cylinders (briefly) and i just figured you would really notice if your wires are gone but maybe its not the same. The muffler is definetly shot, its still good at high rpms but its getting exponentially worse when under any load during lower rpms ie: just after a shift while accelerating.
ps: i checked the compression and after a good 2 or 3 compression strokes it built to 150psi + in each cylinder, does this sound right?

 

Someone around here mentioned that they went through a lot of mufflers when they removed the cat and straight piped it. Put the cat back on and didn't have to replace another muffler since.

Could just be an old, worn out muffler though.

 

yeah i might look into that, a cats job is not to muffle but it does do it to some extent so without it the muffler is doing the job of both. I think i have a cat kicking around somewhere but i REALLY dont want to go welding in this weather.