i am not sure if this would constitute a leak or not, but here is what is happening. if the car is idling at a dead stop, the vacuum will read about 18-15 in hg and sometimes if the a/c is on, it will be even lower (around 15-12 in hg) which seems extremely low to me. if the car is cruising in gear without touching the gas, it holds a consistent 21-20 in hg. does this mean i have a leak and thats why my vacuum is so low during idle or what?

 

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