Greetings, Wrote a few days ago about replacing the ISV on my 87 4kcsq. It ran just as poorly (very rich, much smoke, etc.) after new ISV as before. After checking a number of other items, just for the fun of it, I disconnected the elec. from the ISV. Amazingly, it runs exactly the same! What do you think? Defective ISV? Chris Weathers