95 Discocovery popping thru intake

[vdubinsd]

Hello, found this forum in my search for answers and hope for help-as you can tell by my user name I am a VW guy, but wife loves her 95 Discovery (insert soccer mom comments here, go ahead-sorry-I promise to take it off roading once I get it fixed-I have before )

vacuum advnace fell off and someone how didnt know what they were doing set the timing and messed with the screws to make it run well enough to get the kids to school (1/4 mile away thru the neighborhood)
Since I have replaced the distributor from a 95 I found in the junkyard (was wrecked in the rear, presumed it ran) and set timing. Now when at idle is ok and if revved in neutral sounds ok-BUT-when under load it pops thru intake and coughs-will stay running, but no power and coughing thru intake cannot be good (lean, I presume)
I messed with the allen head screw on the side of the intake, and can get it to pop off load, but cannot get it to not pop no matter where I set the screw (tried from all the way closed, 1/4 turn out, 1/4 turn out, on and on). It does change when it happens in the RPM range, but cannot get it right.

Am I missing something? I presume it is that screw, since it ran great before, but maybe something else was "adjusted"? I dont see any more adjustment screws anywhere and timing is set to 6 degrees

HELP! I need to get this thing running and passing smog, and dont want to throw mass air flow sensors or other parts at it since it ran fine before-but it has been sitting for quite some time (does has have fresh fuel)

Ideas? Comments? Thoughts?
anything will be appreciated at this point....

[Joey4420]

Either a bad distributor, or the Cam is worn out.

[Terrys]

For starters, the Allen head screw is your base idle adjustment, and shouldn't have any effect on whether it's popping back or not. It sounds like you haven't got the timing near right, but generally, popping back through the intake is a pretty good indicator of a shot cam or very worn timing chain.