vacuum problem

[josherino]

I have an aftermarket boost gauge and it is consistant with a peak stock boost of 11lbs and holds at at 10lbs, but my vacuum (negative pressure) is between 11lbs and 18lbs. it wavers randomly, what is the deal with that?

 

[Defiant]

Never bump a thread here.

Your vacuum will waver with the throttle pedal, engine revs, road speed, chassis load and everything else.

If it wavers at idle, you have one of many possible problems.

http://www.iwemalpg.com/Vacuum_gauge.htm

 

[josherino]

my vacuum drops when I push the clutch in and hit the breaks, also when i start up my car the vacuum is either 12 or 14. there are other drops in vacuum but i will have to monitor them and get back

 

[EclipseTrbo420A]

subscribe . same problem

 

[josherino]

vacuum seems to hold constant through gears, but the stock boost gauge flutters while under negative pressure, while my autometer one doesn't so i don't know if i do have a boost leak or some other problem. Also, when putting in my clutch my rpm's drop very slowly and I am wondering if these two problems are related.

 

[Defiant]

my vacuum drops when I push the clutch in and hit the breaks,

Brakes. Check the brake booster check valve.