okay so ive had problems starting my car and i cant get that resolved but i have also noticed that my vac is at 30hg which is as far as my gauge goes and my boost is at 10 peak which i believe is normal.... any reasons i would have such a high vac? its a 2001 audi a4 1.8tqm

 

An engine is essentially a large air pump, and more vacuum is better than less. Leaks are bad, effective seals are good.

I usually see about 25-28inHg at idle.

Its also worth noting that boost and vacuum are measured in different units (in this circumstance) and are not equivalent.

In English units: 1 inHg = 0.491098 psi, or 2.036254 inHg = 1 psi.

 

Carbon build up in the cylinder can cause a increase in compression which will make your vacuum at idle higher.

 

Sorry to hear this as the 2001 1.8T's have a known problem with build up in the engine ventalation hoses. This build up does not allow the engine to breath thus creating an internal vacume as noted below. We refer to it as the "sludge problem". It entails removing all the hoses, cleaning or replacing as needed, cleaning out the oil pump pick up tube and cleaning deposits out of the cylinder head. Not a fun job, also make sure you are using the updated larger oil filter 068115561B instead of the original smaller version--get more oil flow this way. Hope this turns out not to be the issue but just incase we added our 6 cents worth. Have a great weekend.
Loree

 

^The more you know.