Long story short...left Colorado for New Mexico in my new-to-me 1990  
westy Sunday, when 2 hrs into the trip on I-25 I felt the dreaded  
single engine "buck" - one simple stumble, then another 20 minutes  
later, then another in 10 minutes...then every few minutes or so. By  
the time we got to Trinidad, she was stumbling pretty badly , but not  
bad enough to stall out. stumbling was *not* accompanied by tach  
needle drop, and seemed to do it when pressing accellerator after  
letting off. if I pushed the clutch in during an "episode", idle would  
be erratic, surging and sometimes dropping slowly to stall. hard to  
say whether turning ignition off/on made it go away, as condition was  
very intermittent.

Next morning replaced fuel filter and put in some injector cleaner.  
One hour later down the highway, same deal.

Got to Taos, read up and went to Radio Shack for a 22mf capacitor and  
a soldering iron. Also got a new cap and rotor and a set of spark  
plugs just in case. Installed the capacitor (electrolytic, didn't have  
a tantalum), and put in new cap and rotor. thought all was  
well...until about 2 hrs down the road from Taos to Albuquerque,  
syndrome returned but a little different...this time it was not  
stumbling, but hesitation - like a flat spot. pressing accelerator to  
floor seemed to make it "catch" and clear the condition, but it would  
return 2-5 min later.

So I got back in and cleaned the resistive pad in the AFM w/alcohol,  
and loosened the screws that hold it's mounting plate and shifted it  
about 1/2mm to get the wiper on a new track. Ran perfect for about 30  
minutes on highway, but then it struck again and this time it was  
pretty severe hesitation - gas pedal wouldn't rev engine, no power, it  
would just cough. if I let it go to idle it would stall. turning off  
ignition and on again cleared it totally - for about 3 minutes.

So I opened things up again and moved the plate back. installed new  
plug wires for the heck of it. Also got a new O2 sensor, but couldn't  
get the old one off. haven't had a chance to test it yet...kind of a  
pain to have to drive an hour to see if something fixed it.

So, anyone have any recommendations? Also, does anyone know where I  
can get a replacement AFM in Albuquerque?

David

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David Hardy
Planetmind Internetworks
Nedernet, Inc.
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