In idle the car's vacuum in kpa is surging from about 100-20 repedeatly and car has a wierd hicuup like idle to it......any ideas? just started recently all mods have been on for about 2000-3000 k and have seen this issue till now

 

what mods you got and is it throwing any codes

 

intake/ hks bov/downpipe/3inch FMIC/HPT tuned after puttin the downpipe on it set a code and still need to get it tuned but that shouldnt be the reason for idle surges should it

 

do u have the maf relocate and block off for the bov