Long story short: I think I am looking at a bad AFM that I have been testing and trying to get to operate correctly for about 2 months and ran accross a gret link: [www.atlanticz.ca] . It is looking like the carbon trace is wearing out to the point that I get very eratic resistance readings off the output tot he ECU. I have tested the Pin outputs for trace and am getting 180 ohms accross pins 8 and 6 for the entire length. The reference resistor is dead on at 100 ohms. My issue is that when measuring the resistance accross the wiper and either end of the trace, I get measurements that are jumpy (Expected) however they are running from 140 ohms through 550 ohms and jump all over throughout the trace and never linearly fall or raise through an expected range of 180 ohms to 0 ohms. I don't have a known good AFM to compare with so would like a little insight from someone as to the propper behavior I should expect before I go get a new one.
Thanks a bunch in advance.

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Jerr
(1976 280 Z... Shaved and yellow)
www.fishsqueezer.com/zcar
Tri-Cities Washington

Have you tried using contact cleaner on the carbon trace, wiper, & contacts to see if the resisance readings improve in consistancy?
Some have had success by shifting the position where the arm contacts the carbon trace so that it uses a new area for its arc.
This can be done by carefully bending the wiper arm or shifting the location of the circuit board slightly.

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Blue 83zxt coupe .. Eibachs , Tokicos , GReddy stuff, B&M sts, Magnaflow
Orange 77 280z coupe ..

Seattle WA

Been down that road already, Cleaned the whole unit throughout with electronics contact cleaner, moved the board to better align the trace not in the groves that have been dug for the last 30+ years and even tried applying more pressure on the arm contacts to get a better connection. I went as far as to test the resistance with the probe and not using the arm at all but again, I am not sure exactly what the reading should look like throughout the sweep since I don't have another "good" one to compare it to. This is why I am hoping someone else has done this and can give me a feeler.
Thanks

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Jerr
(1976 280 Z... Shaved and yellow)
www.fishsqueezer.com/zcar
Tri-Cities Washington

UPDATE!
I just got in my reman AFM from Motorsport and after installing it, the thing purrs like a kitten again. From all the tinkering and trying to get the old AFM going again, the best cure was just a new board without 30 years of wear that has a smooth resistance curve throughout the range.

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Jerr
(1976 280 Z... Shaved and yellow)
www.fishsqueezer.com/zcar
Tri-Cities Washington