JohnVT

I've done a quick search and can't find this...
what size vacuum hoses do I need to replace vacuum lines on a 2000 4runner v6? I have a p0171 that won't go away. I cleaned the MAF sensor, and replaced the PCV valve and fuel filter. I can't see any leaks in the vacuum, but those can be hard to find.
So how much hose should I buy to replace? Is there a diagram of all the vacuum lines so I don't miss any?
Any place else that others have experience vacuum leaks?
thanks in advance.

stir_fry_boy

Vacuum hoses will usually throw codes like P0440, P0442, P0446 and so on. Those are usually vacuum hoses / EVAP leak stuff. Without looking at the FSM, I don't think that a vacuum hose will cause the system to run lean. Did you clean both filaments in your MAF? How many miles? 99% of the time it is the MAF. Other people have posted that even though they cleaned the MAF, they still ended up replacing it.
You might consider downloading an FSM (factory service manual)
Search this, and it will tell you everything you need to know about the MAF and how to test it with a voltmeter to see if it is bad.

JohnVT

thanks, I'll check out the MAF again, and run the tests...

but I forgot to mention that I also have hesitation from idle. Can the MAF cause that? It's a 2000 4Runner, with only 53K.

ericdg16

I just did a tune-up on my 97 this weekend and replaced all the parts you mentioned.

I just pulled them off 1 by 1 so I couldn't screw up. I pulled off the smallest size and went to autozone and bought 10' of hose then came back and replaced all the other hoses that were that size. Then I went to the next size up and so on and so forth, until I had replaced all the hoses I could get my hands on. Though I live only 1/4 mile or less from autozone so multiple trips don't bother me. My runner has almost 150K so I ended up replacing more than the vacuum hoses.

There was a rough diagram under the hood of my T4R and several in the chiltons I just bought.

I ended up buying 4 or 5 different sizes of hose all in 10' lengths except for the biggest size which I only bought 5'. I had very little left over. Though I would have had a lot of the smallest size left over but decided to replace the windshield washer lines since I had the hose.

stir_fry_boy

Anytime the air/fuel ration is screwed up it can cause hesitation. In your case, you know that your truck is running lean and so yes, it can cause hesitation.