help adjusting the Airflow Potentiometer
Here is a good link to set it.
http://www.landiss.com/mixture.htm
Put it at between 40-50% and just leave it alone!!
I quit and got an idea.
I called the wife and had her start it. While starting I pushed on the P flap an WAM she started.
thank you mercedes!!! I CAREFULLY turned the screw while forceing it to idle. Slowely I lifted my finger to close flap while the fuel mixeture changed. Took about 25 minutes. It also died a few times. Finally got it to ideal on its own. Had wife shut car off then start. Took a few 1/4 turns to get it to start on its own. DONT turn to much u will flud her out.........At first I thought it was something elso so I check the spark plugs and they were sopping wet. Also had good spark and thats when the idea came. ( Upper half for people who need help and made my bad decision) Ok heres were Im at need help!!!....
Did 2 checks 2500rpm
First 68% @ 13.5v @4.1v to 4.5v = average 4.3
(leaned died so richened 1/4 turn)
second 75% @ 13.5v @3.1v to 3.7v=average 3.4
Idle
First 93% @ 13.5v @ .9v to 1.0 = average .9 ( bounced slow)
Second 93% @ 13.5v @ .9v to 1.0 = average .9 ( bounced faster)
Theres the specs what do I do from there Ps2cho

Thanks so much for your help!
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There is a debate whether or not the mixture changes things -- but in my experience and others' too, it does seem to affect the mixture to some extent.
What you really need is an CO2 tester to get the best information. The alternative to this is to use a DMM to read what the O2 sensor is finding. Probe the two cables (underneath passenger seat) and it will flucutate between 0 and 1v. 1v means rich, 0 means lean so you want an average somewhere around .5v.
The last way, and the quickest, is to just set it at 50% and let the system adjust itself as this is the way the system was designed. But as I said above, experience and technical specs don't always hold hands.
The numbers you posted are from what? The X11 and the EHA? I'm a little confused. Either way, they are too far out of range especially if that 93% is true!
EDIT: Oh okay I think I get what you are doing now. It is redundant to use both the % and voltage as they show the same thing. The X11 connector uses a 0-13.5v (IIRC) range. 14.3v indicates lean the way that you are doing it, and 0v shows rich. Take the voltage you get, and subtract it from 14.3 and you get the % you got...See? So its easier just to use the % as both numbers mean the same thing.
Hopefully this helps.
Goodluck!
Last edited by ps2cho; Apr 19, 2009 at 10:41 AM.
Ok lets look at the math numbers.
This is the old math problem I was using from that article u sent me.......duty cycle=[1-(v{pin4}/V{max}]x100%
What your saying to do..........
2500rpm check
first.......4.3v-14.3v=10%
Second..........3.4v-14.3v=10.9%
idle........
.9v-14.3v=13.4%
So if 0%is rich and 14.3 is lean Im running way to lean which is probably y it won start when it cooled down SOOO i need to be at 7.2% to be at 50 percent????
Also did you detach a purge line?
I'm not sure about the purge line...I have never removed it. Concentrate on getting her up and running, wait til she warms up then keep adjusting it til you get 50%. Rich or lean doesn't matter in this case...just get 50%

Ok lets look at the math numbers.
This is the old math problem I was using from that article u sent me.......duty cycle=[1-(v{pin4}/V{max}]x100%
What your saying to do..........
2500rpm check
first.......4.3v-14.3v=10%
Second..........3.4v-14.3v=10.9%
idle........
.9v-14.3v=13.4%
So if 0%is rich and 14.3 is lean Im running way to lean which is probably y it won start when it cooled down SOOO i need to be at 7.2% to be at 50 percent????
The correct method (I am assuming because you don't have a % function on your DMM) would be this:
4.3v/13.6v = 0.32.
then take 1.0 - the above to make it into a percentage:
1.0-0.32 = 68%
4.3v is 32% lean and 68% rich. Make sense? You aren't too far off. Just turn that anticlockwise about 1/6 of a turn if you haven't touched it since and that should bring you to 50%.
To make it easy... 13.6v / 2 = 6.8v (50%) <--- this is your target # to be by within a 10% margin so +-1.36v
Last edited by ps2cho; Apr 19, 2009 at 04:08 PM.
Ok heres the specs at idle I got a 42% and at 2500rpms I got 45%. ......Is that good??? The only problem is my cycle isnt a close loop like the paper says only 3 ten thousands of a movie example 4.5v 4.6v 4.7v So you pick 4.6v and then do your math. Mine moves 5 times does that mean my o2 is bad????



