I was actually watching the tach...looked like about a 100rpm swing w/ the throttle steady. I did replace the rubber caps a few months ago...you're right, they had split quite a bit. The new ones seem OK. Maybe I bought some demon gas somewhere...perhaps I should try some of Dinqua's home brew for an additive. At least if it didn't work I could drown my sorrows.
...my kingdom for fuel injection, TM
