I've been fooling around trying to get my S-AFC dialed but I'm having a few difficulties.
I've noticed that my O2 voltages appear to be low (about 0.8v) at the top of 3rd, but, a data logger shows about 0.86V so I'm chalking that up to a grounding difference or something. The weird thing is the voltages are higher when the car is cooler, I would expect the opposite. If the car is a little cooler then there should be cooler (read denser) air entering and it should run a little leaner (lower O2 voltage). Anyone else notice this? By the way EGT's are about 1550 at the top of third which should be fine, I've heard that they will climb higher in 4th and 5th so i want to be safe. Besides, at the top of 3rd you're doing about 160Km/hr which is a hefty fine if ya get busted imagine trying to tune 4th or 5th?!!
Second, my low throttle settings and high throttle settings are all around +10 with the high throttle ones getting a little higher above 5K. When I had the Al Blaha mas I didn't have the S-AFC and at higher rpm the flapper door would be open and should be exactly the same as the mas I have now, so why am I having to add fuel? Shouldn't I be able to set the high throttle settings to 0 and be the "same" as before?
What are other peoples settings for similar mods as below? Anyone else have to fiddle for changes in weather?
16G, 2 1/2" complete exhaust, '95 exhaust manifold, walbro pump, 17psi on 94octane,

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'91 Laser RS Turbo-"Sound Advice" guy.
www.geocities.com/motorcity/speedway/5051
Turbo + Intercooler = The replacement for Displacement

My A/F always read higher when the car is cold. I beleive that the O2 sensor has to be fully heated to give consistent readings.

I observed the same thing on Michel's car.

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Francois Villeneuve
Le Talon
Working on it...

Also, the ECU will richen up the mixture depending on coolant temp. I can't remember how much, but I do know it has the ability to add a lot of fuel when it's cold..

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1992 Eagle Talon Tsi FWD
Superiority after 60'..
ICQ # 9622983 My Home Page...

Even though you have an EGT, I thought I would pass on a mod for the a/f gauge that would make it more accurate.

I am thinking of trying this out. http://www.gadgetseller.com/gauges/

Let me know what you guys think.

Joe

Mines more accurate...It's a two digit voltmeter. Reads values like 79, 85, 93 for voltages meaning 0.79 etc. I've also got a 3 1/2 digit one but I'm too lazy (or is that busy? ) to put it in.

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'91 Laser RS Turbo-"Sound Advice" guy.
www.geocities.com/motorcity/speedway/5051
Turbo + Intercooler = The replacement for Displacement

Chris, everything that you've mentioned above seems about what I've experienced.. Your settings are close to where mine use to be (before my recent engine rework, with the head now, my maps are all over the place) I too have noticed a variance between the A/F voltages and the datalogger, but still only treat that as an indication of open/closed loop ECU operation for tuning the S-AFC... the EGTs are a safer indication of what's going on for fuel (as long as your timing is not being pulled back at any point). My EGT will peak around 1550-1600 at the top of 3rd (but you don't have alot of time to see the temps at the track)

And yes, with the way the weather is changing now (becoming cooler), it will be coming close to having to make minor adjustments to the AFC settings. I had to do the same thing into the fall/winter last year, then back from winter/spring this year.. all I do is right down what was working before changing it to baseline for next season. As for the voltage readings.. might it have something to do with the ECU changing to another map? (that we haven't set the AFC to..)

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93 Talon Tsi AWD
once again mobile in style
www.geocities.com/MotorCity/Street/1125/

[This message has been edited by Craig Watson (edited September 05, 2000).]

Ok Guys...

I got a intellitronix 02 voltage guage that reads in millivolts from .000 to .999 of a volt this thing is geat I use it in conjunction with my egt. It work great.