I have the same problem, as others also do. I was told to advance the
timing a couple of degrees past specs. And to replace the water temp sensor
two. I did both. I like the timing advance . The temp sensor cost $25,but
no change in preformance for me. It seems that I am always fighting
hesitation or idle surging or cold preformance. A tweek here causes a
problem there.

I have found a happy(?) medium. A tad of surge,let it warm up for one more
minute in the morning,Advance the tinming a tincy bit.

                        Roger Sisler
                        http://stores.ebay.com/rdsrds123
                        Vanagon parts store: 10 percent discount,but
contact               me first for the discount before purchacing