I have a 87 Vanagon with a digfiant efc.  Now that the cold weather is upon
us in Chicago, the sytem is running terrible.  The fuel consumption is
around 16.1mpg (automatic) and the tailpipe is very sooty. ( had been
18mpg)   The engine is surging/chugging and stalling frequently.  I
disconnetcted the O2 sesonrs with no better results.  I also  checked the
temp sensors and they were resonable,( as I did not have the exact temp).
Any ideas ?  The O2 sensor is the 3 wire type, and the collant temp sensor
were new in the summer (I know, that meaningless)

Thanks,

Larry