75w90mantraN

May have to drive around a bit for the light to turn off or code to clear. Faater way is just disconnect the battery or erase the code and then do a few drive cycles to see if it returns.

Curious whether rest of the tuneup (plugs/wires, o2 sensors, air filter?, belts, tires...) net back the lost power you seem to experience. Now that you mention the added ac load. If no trouble code return, but still not enough power, it seems gravity is merely playing with our heads. What's the grade of these hills...over 7%?? I'll punch in 45 mph...maybe 48 on 3rd gear going up 10% dry road with no added weight on decent michelin LTX tread. Rpm somewhere 3k to 3.5k. Ac off.

More story, new glory.

Justin's Fly

Well fixed a few more cracked hoses today. First day I drove it after cleaning the MAF sensor and walla! Now each gear has as much power as it had before. No sluggish driving! All of this to find out that I needed to clean the MAF. The bummer is it seems like I am going to have to start cleaning it every 3-6 months. It might be going out I guess. The light is still on. I might need to drive it for awhile or have the diagnostic computer turn it off at some point.

I still have the oxygen and air/fuel sensors to change this week if I have the time.

Thanks for helping me out. I enjoy to work on the truck but it helps a lot to have folks help me along the way.............I really appreciate that. I will let you know how it works out in the long run.

75w90mantraN

Enjoy that feeling for as long as you can. Look forward to diagnosing the next issue that arises. Part of the ownership.

ZUK

iTrader: (1)

Maybe going back to the factory paper air filter will eliminate the cleaning the MAF ritual.

Malcolm99

I have had this problem before, popped the hood and noted a lot of slack in the kickdown cable, throttle was moving through its entire range, everything was adjusted to its max tension making it impossible to tighten the kick down cable. Solution, remove throttle and kick down cable and bend the bracket that holds the kick down and throttle cables adjustment. Seems like someone tightened the throttle cable to much at some point and when you mash the pedal to the floor it bends the bracket pulling everything out of adjustment. I set mine so adjusters where centred and the bead on the kick down cable was 1/4" away from where the cable protrudes from the sleeve near the adjuster. Truck drives like a different vehicle now and no longer needs me to stretch my leg out to get it to get up and go. Strange they made that bracket so that it could even bend at all, poorly designed due to the angle and leverage that could be applied, you will see it is easy to bend back into position.

old87yota

^^ x2

There is nothing wrong with OEM stock filters.

Justin's Fly

I don't mind stock filters, but they get expensive. I have only bought one air filter since 2008 and it looks the same after I clean it. Not sure what the difference would be after 10 years of having the metal filter....I guess it could go bad. Not sure if I have ever found that it gave me any more horsepower, but I hate buying paper filters and throwing them away. You guys might be right, but they have treated me well in the last three runners.

Justin's Fly

Gonna have to figure out where this kickdown cable is. Tat sounds like a good thing to know for the future.

wyoming9

iTrader: (1)

Kick down cable is for automatic Transmissions !!!

I only ever run the Toyota air Filters if I can`t get those I use Wix

i check them every oil change when they get to bad I replace.

I never cleaned the MAF in 125,000 miles

Justin's Fly

Perfect, got a manual.

Yeah I never cleaned my MAF for the first 110k since I have had the runner and would guess it wasn't cleaned the first 45k that somebody else had it. I have been running around in the powdery dust more often recently. Driving through white powder 6" thick is probably not the best for anything air........ I know it affects my breathing!
Thanks Wyoming

Justin's Fly

So I finally got around to changing both sensors for the exhaust. Probably the easiest exchange I have had on the 4runner. Had to clean the old gasket off with a wire wheel but otherwise it was a piece of cake. The interesting thing was my RPM's were around 1.25 to 1.5.......and they dropped to 0.75 immediately after. Supposedly it might add mileage, we will see about that.

After cleaning the MAF awhile back the check engine light went off in the middle of hunting. The day after......running in about 80 miles of dust it turned back on again........DOH. We will see what happens with the new sensor changes.

habanero

Just curious....when you are cleaning the MAF are you just cleaning the sensor bulb that is readily seen or are you cleaning the 2 not-so-readily-seen very delicate wires too?

Justin's Fly

I probably spend more time cleaning the "bulb", but also clean the other two "holes". I might want to clean them better. I usually shoot a few shots of MAF sauce into either hole and turn it over to dump out liquid.

habanero

The first time I cleaned the '99's those holes were so oily from the previous owner's K&N filter I couldn't even see the tiny fragile wires....

It's a cruddy pic, the camera didn't want to focus.
MAF sauce sounds reasonable- they're very delicate.

Justin's Fly

Hey thanks. I might clean it better and check to see if I can see the tiny wires. Still scratching my head on the K&N oil filter. Might have to change that and see what/if any difference. Funny it hasn't made the check engine light go on for the last 110k. Did you have the engine light on with your oily sensor?

habanero

Yes, check engine light popped up a couple of days before we bought it and hesitation taking off from a stop a little after that, ran well otherwise at that point. I don't know if it had been cleaned before then, it had about 160,000 miles on it.

Justin's Fly

Check engine light has not come back on? And you replaced the K & N filter with paper?

habanero

Many years later it came back on after an overly dusty trip in Colorado dirtied the wires again so yes, in our case cleaning the MAF solved the problem. We made sure to get those wires clean (did I mention delicate?)- they were completely black and oily- and did replace with a different filter, no more K&N.

Not saying it's your problem, just know a lot of people miss those wires and only clean the bulb. Here's to it solving your hesitation.

Jomoka

On the '99 I think we've experienced both ends of the spectrum on oiled K&N style filter issues.

When we bought it, the MAF was fouled from an over-oiled filter. Oil hits it, gets burned, that creates a little 'jacket' of soot that insulates the wire from the air, and slows the response down. So it is slow to react to the pedal going down and you get a lean bog/hesitation. And probably, a rich spike when you let up on the pedal, but that isn't very noticeable. And when it gets bad enough, a growing hesitation to the gas pedal and a CEL.

And then after a bunch of very dusty trail driving out in Utah, I think the dust overwhelmed the (properly oiled) filter - drying out the oil, and uncovering the K&N style filter's nasty little secret - that when it fails, it fails in an 'open' manner - letting dust into the engine. It began to lose power, hesitating, set a CEL. Looking at the MAF revealed fine dust coating it here and there. Cleaned the MAF, replaced the filter with a new paper one, it was good again (other than whatever wear it put on the rings from ingesting dust).

The good thing about a paper gasket is the failure mode. It just slowly gets clogged up and you lose power due to a lack of air. But whatever air gets into the engine is at least still clean. And if it really gets clogged up out int he middle of nowhere, you can just take it out and whack it against something and knock out a lot of the dust stuck in it, and it's pretty good again.

The oiled filters? They're either too oily and causing problems, or not oily enough (and this can happen int he middle of a trip) and causing problems.

Jomoka

And I'm not an automotive electronics expert, but that bulb is jsut an air temp sensor, it has very little effect on what the MAF sends to the ECU. The vast majority of the data is collected by how quickly the tiny heated wires heat up and cool down as air passes over them.