Originally Posted by GraphiteGhost

One sure fire (pun intended) way to check for VAC leaks, spray LIGHTLY carb cleaner around the vac hoses (while all the intake tubes are still connected to the front grill air intakes with any wind blowing towards the rear of the car). Keep the spray AWAY from those grill intakes or you may get a false reaction. I use the spray without the thin tube nozzle, the spray is wider and less is directed (a very small amount will cause immediate increases in rpm if there is a vac leak). Hope you do not have one BUT it will help you troubleshoot for sure! Good luck nailing this down!

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