88T4R

I have about 1200 miles on my rebuild and i have the timing set at its best which is 10 BTDC, I tried at 12, but it was too lean, also I just got a new full exhaust. Anyway my question is my exhaust from the tail pipe smells very rich still and it is even after an hour or so of driving it still smells rich, what could be causing this? I was thinking maybe the o2 sensor is bad, but since I have the timing set correctly my mileage is like 20 in the city, just wanted to get some opinions! Thanks!

88T4R

anybody?

scuba

Try adjusting the AFM whatever the specific toyota one is called, could be adjusted wrong causeing it to be to lean.
http://www.lcengineering.com/TechNotes/TechNote19.htm
First paragraph right there should help...
Its a start

Edit, This ones a bit better with pics and such
http://www.4x4wire.com/toyota/minutemods/afm/

Chapman88SR5

Sorry to high jack but...

"Turn the gear counter clockwise to loosen the spring and richen the fuel mixture."

So if he is running too rich, would he turn it clockwise then???

88T4R

thanks guys, I was trying to think what I else I could adjust to lean it out, didn't even remember about that, I will try it tomorrow, thanks!

88T4R

It also makes sense because it is still set for the stock motor and mine isn't stock anymore.

88T4R

seems like I should already be running lean because I have bigger valves and a little more displacement than stock, so you would think it would be asking for more fuel. Anyway I will try it and see if it helps! Thanks for the suggestions!

scuba

Afirmative.

Yeah, 88 at least give it a shot.
Dont forget to mark it before you start going and turning it though, Good luck and let us know what happens

Chapman88SR5

This would be the same for the 3.0 correct?

Pistonman

This does not make much sense. You say advancing your timing is changing the A/F mixture? I would advise against adjusting the AFM. Been there done that.
I think you have another problem.

88T4R

no the timing is not effecting it, when I was getting the timing set it would smell rich from the tail pipe no matter where I had it, the timing is just set where it runs the best, gets the best mileage and doesn't ping. I have it set perfect now I just need to adjust the AFM.

Pistonman

When performing the standard mods (cam. head, etc), most people want to richen the mixture a couple clicks. Unless you are at high altitude, I would still think you have another problem - possibly one you had before your rebuild.

scuba

About the 3vze question, this is what i just learned, and you should do the same http://www.customtacos.com/forum/showthread.php?t=56229

Oh and 88, Also it might be an idea before you go ripping that afm open to check if the cold start injector is sticking open after your running...that would make it smell rich.
check that, if nothing i would move to the afm

88T4R

how would I check to see if the cold start injector is sticking?

scuba

Im really not too sure, my first thing would to be start it up and then pull the CSI itself and if its squirting gas, then its sticky.
Second way i would do it, would be warm the engine up, like normal operating temp. Then shut her off, pull the injector maybe have a friend, little bro, sister, what have you, turn the ignition on as your in there checking for fuel coming out of it.
ie, if the engine is hot, no fuel should be coming outta it (but im assuming you already know that)
or you could do it the hard way
http://personal.utulsa.edu/~nathan-b...29coldstar.pdf

blacklabel

did you remove your cat?

88T4R

no I still have the cat on, thanks scuba I will try that, I was thinking about pulling the csi and setting it in a cup or something, starting it and seeing if its stuck. thanks I will let you know whats gong on!

88T4R

ok so I have some info, took it for a short drive then came home and pulled the cold start injector cranked it about ten times and got it to run for about 5 seconds and it didn't spit a drop of fuel so its not stuck open. Then I look at the afm lid, I haven't opened it yet, and I see that it has been opened and resealed again by the previous owner. So I am thinking this must be the problem and I will lean it out a little and see how it is, he must have had it running rich!

scuba

HAH, thats baller, kinda.
Let me know what happens

4Crawler

iTrader: (3)

In closed loop mode, the O2 sensor is what controls the air/fuel mixture:
- http://www.autoshop101.com/techartic...larticles.html

What brand of O2 sensor is in there now and how old is it?