Pirate 4x4 banner

AFM how do you know, to rich or to lean?

879 Views 6 Replies 5 Participants Last post by  Blackulua
I have played with the AFM after putting headers on my 86 22re and made it 1 click richer.After 6 months now it seem to be to rich, i've lost a little power and when you give it gas, it fills like it looses power before it picks up. It didn't do this before,so I reset the afm back to stock.But its still doing it.It sound like it runnung to rich and tale pipe is jet black,not dark grey. Should I lean it a click or two?:confused: Is there a way to tell if its to rich or to lean.Like the color of the tale pipe,etc? I've leaned it 1 click today,from stock,but didnt have time to see if it helped. It does seem to run better while it still cold, before warming up.

p.s. I did search but didn't find the answer I was looking for,so flame on if you must:mad:

Thanks Larry
1 - 7 of 7 Posts
Take it to your local Smog station--- have them just do a test- they can tell you if it is too rich/lean--
Mixture meter

I was in the same boat and found lc engineering's mixture meter kit. Its a little over priced but you can pick up a mixture meter for about $35 at a local auto parts store. Thats about the price a smog station will charge you for one test. It hooks directly to your o2 sensor. Here is a autometer gauge.
See less See more
There's a much better way -

Attach a DVM to the Vf signal

The Vf is the "trim" signal of the EFI.
It tells how how much the EFI is moving off its base signal to make the 02 come out correct.

I think you can search on Vf - Im kinda tired (today) of re-writing posts on this subject...

There was a good write up on one of the Supra sites - its those guys who discoverd and documented this function (the factory doesnt want you to know about it I guess)
I drove it today and its doing better but air temp seems to have a real affect on how it runs (power) Any idea why? You know warm at mid day and cooler at night.It seems to like cooler air .
I have the LCE Fuel mixture Gauge hooked up to the O2.Ive adjusted my AFM leaner because my plugs was running rich.The gauge would show rich on throttle and on idle below or half way on the reading other than that the truck has been running excellent with 127,000 miles.
1 - 7 of 7 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.