1998 S70t5 Inches of Vacuum for s70

s70fanman · Post by **s70fanman** » 05 Dec 2013, 16:52

Gentlemen-
I need to know how many Inches of Vacuum a s70, 2.3 litre turbo motor is supposed to have. One of the guys at IPD told me 20-22 Inches in neutral idling warm. I have heard anything from 18 to 25 Inches and I would like to know once and for all as mine is 18 inches steady and I would like to know if that is acceptable or not.

Post by **jreed** » 06 Dec 2013, 04:56

I have a different model (855), different year ('97) and different motor (2.5L light pressure turbo), so my opinion may not be of any use in your situation, but I would say anything between 18-22in Hg is typical. For what it's worth I noticed about 6 months ago that the vacuum at idle seemed to increase about 1in Hg after I cleaned out the throttle plate. You could also check for vacuum leaks (assuming you haven't already done that). Good luck!

Post by **phils94850** » 07 Dec 2013, 06:16

Agrees with jreed.. anything between 18-22 is good, higher the better

Post by **northernlights** » 07 Dec 2013, 18:10

s70fanman wrote:Gentlemen-
I need to know how many Inches of Vacuum a s70, 2.3 litre turbo motor is supposed to have. One of the guys at IPD told me 20-22 Inches in neutral idling warm. I have heard anything from 18 to 25 Inches and I would like to know once and for all as mine is 18 inches steady and I would like to know if that is acceptable or not.

Mine is a solid 19" Hg at idle. It's a 1994 850 Turbo. In my experience, 20" Hg is typical for a stock low-performance engine in good condition. I have never seen 25" Hg on any engine. With a big cam and insufficient compression and one may quickly get down to 10" Hg or less, but that's a different story.