On my 89 Cougar, I pull off the line to the brake booster and use it. I cut the top off a soda can, put it in the spot behind the shock tower, put the vaccuum line in it, start up the car, and pour half the can of seafoam into the can. If it doesn't stall, then I turn off the car as fast as I can, and wander around for 15 minutes (if I stay there, I can only wait about 12 seconds before starting it up). I start out with the car semi warm (running about 2 minutes from cold), maybe 1 or 2 bars on the digidash temp gauge).
I don't have a picture, but on the big black metal round thing the brake master cylinder mounts to, there is a large (in terms of vaccum lines) line that connects to a plastic plug that goes into the booster, that is the best one to use. I don't have much luck on that car with the PCV valve, tough to get to.
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