SO IPULLED THE PLUGS ON MY 95 4RUNNER 3.0 V6. PLUGS ARE LESS THAN 1 MONTH OLD WITH LESS THAN 1 HOUR DRIVE TIME ON THEM AND THEY ARE BLACK. I THINK THAT MEANS IT IS RUNNING RICH ( BUT NOT POSITIVE). ANY WAY TO GET THIS THING BACK TO WHERE IT IS SUPPOSED TO BE FUEL WISE?

 

If you decide to read much on YT you'll find (on average) you're not going to get great mileage, anyway. But, to solve you're richness may be real simple.....or not.

You changed the plugs, but how old are your spark cables, cap, and rotor? Are you having any running issues; poor idle, loss of power, is it related to temperature, is it hesitating or misfiring, etc.? There are a number of EFI components/systems that are related to fuel/air mix that could be the reason for the richness. You have a throttle position sensor, coolant temp sensor, fuel injectors, volume airflow meter, cold start injector and timing switch, ignition and timing, oxygen sensor/s, catalytic converter, and so on. But, first we need to know how it's running.

There is an online factory service manual with a troubleshooting guide provided via a link on this forum's main page that you can look over. When troubleshooting, run down the list in numerical order (lowest to highest) for the things to inspect. Look under "Others: poor fuel economy".
Link on main page....
https://www.yotatech.com/forums/f116...umbers-102344/
Direct link to guide...
http://personal.utulsa.edu/~nathan-b...63troubles.pdf

 

The truck runs fine under power. When idling, it does stutter every one in a while (about every 45 sec) and after the stutter comes a small pop that sounds kinda like the last kernal to pop in microwave popcorn. Once i give it gas, it runs good and the pop goes away until it returns to about 800 rpm idle. Cap,plugs and rotor are all brand new. Just bought them about 1 month ago.

 

 

How to fix richness huh......well give it all to me then its MY problem $$$$

 

O2 sensor is what tells the ECU what the air/fuel mixture it and it adjust the fuel accordingly. Test or replace your sensor. Install an Air/Fuel meter and you can see if your engine is running rich or lean:
- http://www.4crawler.com/4x4/CheapTri...es/index.shtml

 

Well this will take care of most of your richness:

 

Fixing richness? Get a girlfriend... should clear that richness right up.


How old is your O2 sensor?

 

clearly this is a tire pressure issue

haynes manual is your friend. optionally http://personal.utulsa.edu/~nathan-b...fsm/index.html

not to be a jackass but it doesn't seem like you've looked around much before asking this question :p

 

i could help you out with your richness problem

but seriously i you should try replacing your o2 sensor

 

I'm really new to this. I have asked a bunch of different people and have heard all kinds of different things including timing, valve lash, clogged fuel lines, old gas, and bad injectors. I do realize it seems I haven't looked much but with all these different options, I relly don't know where to start, so figured go to the guys with Yota in the name. Honestly this is the first time I've heard o2 sensor. I knew it was there, just didn't realize it could cause my fuel to be that rich. Thank you all for your help and humor. Great comebacks.

 

lmao...
that and a being a college student and you'll never have to worry about it again
should clear it all up

ya use yotatech
one of the few places you can post newb questions and not get killer flamed, dont even try pirate
youll get 10000 replies of "search" and "your an idiot"
no offense to you
pretty mucn anyone thats not a certified mechanic will

 

sounds like either the blinker fluid or the muffler bearing to me...

You said the plugs were black, what has your exhaust looked like? When your running rich your exhaust might not be too discolored normally but under load or at WOT it will be a bit more brownish.

You might want to do a compression test in addition to the O2 sensor, see if you have any oil leakage also since black plugs dont necassarily mean running rich

 

exhaust is clean during idle and when under power. I'll keep checking different things. I really do appreciate everyone's patience and help. Thanks again.

 

muffler bearing..

you shouldn't be having any problems with that. is there a grease fitting for it?

 

While underneath looking at the o2 sensors, i noticed a small exhaust leak about 3/4 in in in front of the rear o2 sensor. Does this have any effect on the idle or fuel mixture?

 

SUre can, why? If exhaust can leak out, air can also leak in. Air has O2 in it, sensor sees the extra O2 and tells the ECU to increase the fuel mixture to compensate.