When it's been doing it, take off the fuel cap.  If you get a whoosh sound as
the tank sucks air in, you are getting a vacuum in the tank.  Two possible
cures. Hard way: crawl down among the mud/dust/spiders, remove the tube that
goes from the carbon canister in the rear wheel arch (part of the smog equipmt)
to the fuel tank, push a fine wire through it all the way to the tank, clearing
it of bits of broken off carbon, so allowing the tank to suck air in through
the carbon canister as your fuel pump sucks fuel out (mixed with small bits of
carbon to get the fuel filter all excited)- until more bits of carbon break off
from the canister and block the tube. Engine working harder = bigger vacuum =
bigger bucking and skipping.  Physicists could explain why it's worse in hot
weather. Easy way: take off fuel cap, listen for whoosh, nod, replace fuel cap
with cheap plastic 'emergency cap', having reamed out breather hole to almost
1/8 inch with the thing for getting stones out of horses' hooves in your trusty
Swiss Army Knife. Never drive through bushfires.  My emergency cap has been on
for 2000 miles and I haven't had a buck or skip since.

Bob in Oz.
84 Wasserboxer poptop camper

-----------------------------------------------
This message sent through Adam Internet Webmail
          http://www.adam.com.au