99 4runner chirping/squealing

I have occasional chirping and squealing from my vehicle. I'm not much of a mechanic, but when I brought it in recently for some other work, they said my belts were fine. I was reading articles about other Toyota models from the same year that have issues with the automatic belt tensioner. Has anyone ever heard of similar problems with the 4runner?

My check engine light just came on last night so I will bring it in tomorrow to see what that is all about.

I'm also getting some shaking when braking, especially on downhill slopes. It seems like when it rains it pours, so hopefully this won't set me back too much.

...currently 126,000+ miles...

You didn't say what engine you have, but the tensioner bearing going bad in the older 22R series 4 cyl engines was common. No reason it couldn't happen in others.

sorry... v6 3.4l

If that is the case, is it an easy fix? Any estimate on costs?

Go to the Factory Maint Manual thread near the top of the main page.
Use it to help you locate the tensioner if you don't know where it is, make sure that's the noise source, then you can probably replace it yourself using the manual.

I had a diagnostics run... it came back with P0171. I read up on it and learned that in most cases, it is a dirty MAF sensor. I had brought it into the shop who ran the diagnostics... put about a grand in to it... picked it up.. engine light still on. they did a whole lot of preventative maintenance, but didn't fix the actual problem I brought it in for...

so... I still have the problem, and it seems to be making other things bad/or I have other problems as well. I'm starting to have more and more power problems (ie I hit the gas and barely move) and then all the sudden it will work fine. I'm also getting detonation on occasion during the most significant of the power loss.

It decided to stop starting on me, so I went and got a new battery and MAF sensor cleaner. I put the new battery in and it started right up the first time, but was hesitant the next time. (this was yesterday so I haven't seen what will happen today) I heard sometimes there are bad solenoid cables in the starter assembly that get corroded?

I attempted to clean the MAF sensor, and maybe someone can help me on this. the sensor is connected to a larger box (is that the air box?), so unless I want to take more apart, I could only take off the connecting hose and spray the cleaner inside while it still was under the hood. Is that all I need to do or is there more to it?

I'm now also getting squeaking when I reverse. It sounds like it is coming from the rear passenger side - hopefully just breaks?

Any other advice? Currently about 146,000 miles. I'm pretty clueless when working on my car. I'm trying to learn as much as possible.

anyone?