vacuum leak??

[oms]

hey guys, here\'s the run down... so the other day,just after getting my car back from the shop to have a new thermowax and a cracked piece in the throttle body replaced (along with tuning the start up maps on the haltech) i was driving out with a friend behind me.  the engine was around normal operating temp. I was accelerating just past 3000 rpm when the exhaust note changed to a series of loud pops/crackles. my friend, who was following behind me, said that he could hear it from his car and noticed some some along with it ( this sounded much different from backfire). i pulled over and couldn\'t notice anything which seemed off, except for my bov\'s adjuster screw was loose and the valve was running at its softest setting. i tightened it up some what and everything was fine after that. The next day the car,which just went to the shop for a high idle and was idling around 800rpm, was idling around 625 and backfiring a lot. today i checked the resistance on the BAC valve and it\'s reading between 1 and 2 ohms, which is what i have heard it should read. i have yet to determine whether or not the solenoid is sticking. When i disconnect the vacuum hose from my BOV the idle moves back up to 725-800 ish. i really i have no idea what to make of it. I am fairly new to rotaries and don\'t know a lot about the air recirculation/bypass systems used by mazda.  i don\'t know if this helps but when i hook up the BAC valve harness the motor sounds like it has lifter tick (yes i know there are no lifters), this goes away when i disconnect it.
The motor is a 1991 turbo 2 j-spec with a haltech e6x:cheers

Sorry about the essay!
 any info would be greatly appreciated