Thread: which gauges?
View Single Post
Old 07-29-2020, 04:14 AM   #8
4/86 SE-V6 2 tone 4x4 HB
Deerhurst's Avatar
Join Date: Apr 2013
Location: Oregon
Posts: 7,445
Vehicle: 1986.5 SE-V6 4WD D21, 2003 Audi A4 Avant 3.0 Quattro
Thanks: 893
Thanked 922 Times in 840 Posts

Not only can you help economy with a vacuum gauge but you can diagnose a whole lot of things with one. Your engine depends on vacuum. Rough running at idle, vacuum gauge has lower than normal vacuum? Check for vacuum leaks. Blip the throttle and it should go down and then when it comes back pass the normal idle point then return to normal. If it doesn't this can signify a different issue. If the needle wiggles around at idle you have either a huge cam or bad valve sealing. It's also fun to watch. My truck pulls about 22inhg and idle with a slight, barely visible, fluctuation due to my mild cam.
1986.5 SE-V6 4X4 D21 Hardbody
Pacesetter Long Tube Headers
Morimoto Mini D2S HID Projectors and Hella 500s
Deerhurst is offline   Reply With Quote
Thanked by:
Foul_Mouth (07-29-2020)