Full Engine Pulley Replacement == Massive MPG Increase

I changed the pvc recently, no change. The urd fuel pump kit is sitting waiting for me to put it in. No oddball giant tires. I do have a tiny crease in the body near the rear bumper so there's a tiny bit of air drag from the bumper not aligned to the body perfectly. But that's not gonna affect mileage much if at all. I run an occasional can of jectron like I did this weekend because I needed to make a hour drive.

 

That seems like really low MPG?
Have you hooked it up to a scanner?
What is the LT Fuel Trims?

I’ve heard it had to be really high like 25% before you get a code?

Seems to me, something isn’t right?
I never drove an XRunner, but I can’t see them being that much different?

 

I haven’t tried figuring out how to look at the fuel trim. Definitely no codes every time I looked. Xrunners sit lower, have different ratio differential, low profile 18” wheels. Really it drives like any sports car I’ve ever driven except less power.

Feeling like a thread jacker.

 

Just replaced all my pulleys while changing out my radiator....I guess we'll see.

 

Wow mine had 223000 miles on original pulleys and belts. That's good to know since I have a dayco kit for my tundra. My 06 Tacoma is in middle 0f a edelbrock super charged 416 LS3 transplant will post some pics soon as we finish motor mounts and drop it in.

 

Great to know, mine is at 172k and the factory pulleys/tensioner are quiet. Let us know what you think of the Dayco accessory belt kit.
Also let us know about your LS swap, would love to see that! Do you have a thread on this already? Please linky.......

 

I do all my pulleys and belt tensionor when I do a drive belt. I used to be a service advisor and have seen it all working in a service facility.

 

In case anyone is curious, I used Continental part ADK0033P: http://www.rockauto.com/?carcode=1431544&parttype=10660

 

Might want to clean out the MAF and when the last time you did a tune up? You should be able to log your short term fuel trim and long term fuel trim with a scanner.

 

Spark plugs for sure and replace your VVT solenoids.im thinking that is the reason for your atrocious fuel economy.

 

Cleaned maf & throttle body, replaced plugs, changed gear oil, checked for wheel drag, 6 month oil changes, air filters good. None of it made a difference. The only thing that makes a difference is when I use jectron and drive like a grandma. Then I might get 12-13 mpg.

 

No to thread yet new to.the group. Will post one soon really busy at work. I refinish automotive and fine wood work in my shop and iam swamped just keep ordering more parts lol

 

I thought mine were fine, couldn't hear anything obviously abnormal (my Taco is at 111K). But loosening the belt and spinning them by hand, it was clear one was bad and two were marginal. Check it out next time you change the oil, you may be surprised. I didn't need to fully remove the belt to do the check, just locked the tensioner using that super handy spot they have to insert a rod to keep it loose, then go to each pulley and keep the belt out of the way while spinning them. Easy peasy.

I don't think mine were going to fail catastrophically anytime soon, but bearings that have clearly lost their lube have to go IMO.

 

You should log your fuel trim and see if your running rich/lean than go from there.

 

Will check this next time I have reason to open the hood, thanks for the tip.
About releasing the tensioner, I use a 14mm socket and breaker bar on the false nut conveniently molded into the tensioner arm. Where is this place to insert a rod and keep the tensioner arm back? I always just wrapped a bungee around the end of the breaker bar to hold it back lol.

 

Take a look at these pics of the tensioner assembly and you'll see that approx. 1/4" hole where you can insert a rod or allen wrench once you have the tensioner arm rotated CCW about 70 degrees. I used the bolt on the tensioner pulley to loosen it, probably not the right thing to do since it could tighten the bolt, but in any case once you've rotated the tensioner arm enough the rod can be pushed through into that spot on the casting and it holds it there.

 

I monkeyed with this a little today. Long is 3.9 at idle, 2k rpm 6.3, then went down. 3k rpm about the same. Short -2.3 idle, -3.9 at 2k rpm. That's sitting there reving the engine, not driving. I have no idea if it's good or bad, my first time using those functions. Apparently my $400 snapon obd scanner doesn't have a record function even though it wasn't exactly cheap.

I did find my fuel pump resistor out of spec, reading 1.0 ohm, supposed to be .7-.76. I'll get that replaced and see if anything changes.

 

Swapped in the new fuel pump resistor, no change.

Last weekend I replaced the plugs, probably early, I didn’t record mileage when I did them before, so probably at 2000-2500 miles. I removed the pvc hose, found one end swollen, cracking, fits loose. I repositioned the hose clamp to get a better seal for now until I get it replaced.

When I topped off the gas tank, mileage calculated to 13 mpg, whoo hoo. So a slight improvement over in the 10.5-12.5 range. The next couple fill ups should give me a better idea if that hose is my culprit.

 

Notice any difference?