if your hunting for a vacum leak just use WD40 or some type of penetrating oil, thats what i use. I know it can be messy but it will eventually evaporate for the most part and does fill in any leak to give you a chance to listen for any change in engine.
Using anything as flammable as ether or propane is suicide...
This reminds me of back when i heard about service stations servicing peoples Air Conditioners and filling them with propane, sure it will work the same as freon but the HUGE drawback is it's flammable!!!! Get a leak and then spark? BOOM!
get the picture?
use your brains guys... this is simple common sense.
ok as for your engine surging problem?
is there not an air control valve on these trucks? kinda works the same was as an idle air control valve does on a car?
try looking there...
good luck
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