cool thanks guys ill let you know whats up

 

Spiffy! We'll be here!

(oh, and if you didn't read between the lines of Jamie's and my babble, it'd probably speed up results if you reset the ECU)

 

yeah im gonna do that in the school parking lot

 

update......

still nothing. i pulled the EFI fuse and i still have terrable gas mileage. just had to fill it up and i had about 160 miles from a full tank. so im changing the 02 sensor.
PS i also cleaned my throttle body

 

Bummer, but that's how this stuff goes. You have to work through the options, and eventually you'll hit it.

Hang in there and let us know how the O2 sensor goes!

 

ok, well my next question is where can i get one? any auto store? or do i have to go to the dealer?

 

The best prices that folks have found come from URD USA:

http://www.urdusa.com/product_info.p...s_id=430006000

Make sure you get the correct one for your rig... you'll want the FRONT one if there's a difference.

ONLY use Denso (they're OEM) and do NOT try the "universal" ones. They will be nothing but trouble.

 

Ditto on that. The installation is super easy.

 

ok wow i really appreciate it guys thanks alot.

ill probably order that this next weekend

 

I have had this same code and during the past few days my CEL has been coming on and then turning off. Since I don't carry an OBD scanner around in my truck when I head to autozone to check it the damn thing is off already.

I only know that I had the code because I was able to check it a few weeks ago.

I did clean the MAF as well and the TB. I seem to still be getting around 300 mpg on a full tank of gas.

Any ideas?

 

it could still be a 'bad' MAF - they are cheaper than O2 sensors (AF sensor)

Bad mileage could be related to other things - old, burned up plugs...........

 

300 MPG??? WOW!!!!

Ok just kidding, I knew what you meant. If you are still getting normal mileage, then I would slide under there and check the connection and the wires as best you can. Reason is with a cranky O2 sensor your MPG will definately drop.

 

A CEL shows up only after the code first goes through a status of "pending". Most readers (not all) can read the "pending" codes before they become a CEL. Head to AZ and ask them to look for 'em... something could be there, and it may not be the code you last saw.

DZ's right... the source of the CELs sounds like it may be an intermittent wiring. The issue would have to be there for awhile (100 miles of driving or more) for it to affect your fuel trims and thus your mileage. Given that the mileage is fine (VERY fine!) I'm almost inclined to say "don't worry about it", but again, the code may not be a P0171.

 

This morning the cel was off and then this evening it turned back on. I was unable to get the code read though.

I may go rent the scan tool from Autozone and carry it around in the truck for a couple of days.

 

I had the same code and a "new" MAF from the junkyard for 60 bucks fixed it. It takes 5 minutes to replace. I would try this before I bought an expensive O2 sensor. Refer to this thread for part numbers

https://www.yotatech.com/forums/show...ighlight=P0171

Lots of toyotas have the same MAF sensor as the 4runner like the camry for instance and they are easy to find.

 

well i changed my plugs and cleaned my MAF and throttle body. im getting about 100 miles on a full tank.

 

(thanks for posting back here versus the other thread!)


Okay... something is VERY wrong now. 180 miles on a tank is bad enough, but now you're looking at just 6mpg.

That's well into the zone of having a fuel leak, someone siphoning your tank at night, something MAJOR.

With that kind of mileage, you should be smelling gas VERY easily. Do you?

fwiw, a bad O2 sensor will not cause THIS much of an issue. Blowing this much fuel is beyond what the ECU can dish out.

 

i dont smell any gas and i dont have a leak cause i would see spots and stains on the drive way. i might be a little off but its bad

 

Well, okay... but 100 miles on a tank versus 180 miles on a tank are much different numbers with much different potential issues.

Seriously, I can tell you why I only get 180 miles on a tank (I thought it was the O2 bung leaking, I've since found out it's a burned harness) but if you're getting say, 150 miles/tank or LESS, then something is drastically wrong.

Did you order the O2 sensor? An O2 sensor issue can push you to 180 miles/tank.

 

no im ordering it in a few days. i have to check how many miles i get on a full tank but i know its not good. i think at half a tank im at around 70-80 miles