I cleaned my 740's throttle body last night using 3M throttle body cleaner. It worked great, it was moderately dirty, but it all went just fine. I went to the local pick n pull to get an extra throttle arm connector before i started (the one with 2 plastic arms that go over the ball joints) due to the wonderful suggestion the FAQ's on here made that the plastic could break if too old, and despite my carefulness, IT DID) so thanks to the FAQ's and brickboard for the advice! Anyway i pulled in my son's 240 for the same treatment. I have had it to the volvo dealer because of the persistent slight miss upon starting from a stop. They put new plugs in it about 3K ago. It starts great, runs fine when the gas is depressed while driving w/ no missing. The problem it has been having is when you come to a stop sign and push the gas to go, there is a slight miss or hesitation before going. So back to last night. I took his throttle body off and it was pretty dirty. I thoroughly cleaned it with cleaner and a toothbrush till it shined and blew out the vaccum line connectors. Upon re assembly though I found that the tiny vacuum hose that goes on the right connector of the TB was completely severed down around where it goes to the vacuum cannister. I don't know for how long it has been this way, but looking at the dirt and grime on both severed ends it appears to have been a long time ago. I would not have discovered it, since it was up under the air box unless I had given it a slight tug and it pulled right out. I went to the local AutoZone and got a replacement hose for it and the larger one while I was at it. Dropped the vaccum container and replaced the hoses and re assembled everything. I then took it for a spin and I swear the miss is virtually non existent.

My questions are: I know that both the vaccum hoses on the throttle body go to the same place, but could the broken tiny vaccum hose have caused the slight miss I described, or is the decrease in the miss probably due to the cleaning I gave the TB? In fact, what is this tiny vaccum hoses' function?
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93' 240 Classic Wagon 220K & 92' 740 Wagon Regina/Rex 90K