I also thought that since this is a diesel and the vacume comes from a vacume pump that it wouldn't loose vacume at full throttle, so thats why i didn't use a check valve.

I dont know if it is supposed to, but with the ac controlls on, the heater circulation pump (on passanger side) is running.

[Edited by diesel lover on 06-04-2001 at 09:04 PM]