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Galligher · 07-10-2001, 10:12 AM

I have a 91 LX with an AOD. I have not had it that long and it has a hesitation/backfire every once in a while when the engine is under load. I hooked a vacuum gauge up to it last night and got a steady 15 PSI (Vacuum) at 800 rpm idle. If I "goosed" it, vacuum dropped to nothing and then raised to 19 (~1000RPM). When idle came back down, it dropped back to 15.
I tried using propane, but it did not work. I opened the line that normally goes to the diverter valve and let propane in it and noticed no increase in RPM???? I then sprayed carb cleaner in it and again nothing??? I also noticed that when I disconnected the line vacuum did not change. This is what is really leading me to believe I have a leak, or is it that the line is small enough not to have a great effect.
Any help???
Thanks,
Brian

07-10-2001, 10:12 AM	#1
Galligher Registered Member Join Date: Dec 1998 Location: Ft.Wayne, IN Posts: 12	Another Vacuum Question I have a 91 LX with an AOD. I have not had it that long and it has a hesitation/backfire every once in a while when the engine is under load. I hooked a vacuum gauge up to it last night and got a steady 15 PSI (Vacuum) at 800 rpm idle. If I "goosed" it, vacuum dropped to nothing and then raised to 19 (~1000RPM). When idle came back down, it dropped back to 15. I tried using propane, but it did not work. I opened the line that normally goes to the diverter valve and let propane in it and noticed no increase in RPM???? I then sprayed carb cleaner in it and again nothing??? I also noticed that when I disconnected the line vacuum did not change. This is what is really leading me to believe I have a leak, or is it that the line is small enough not to have a great effect. Any help??? Thanks, Brian