Is the engine supposed to do this or not?

I know this is completely in the wrong car forum, but since this is my forum and knowing you guys know your stuff, I trust your answers.

Here's the deal. Buddie of mine is looking at getting into the honda scene by looking at a 1990 Integra LS with a B18 130hp version sedan. 175,000 miles roughly. It's in great shape besides the broken passenger mirror, ripped seat and a few minor rust spots. It even has the stock radio in and looks as if no racer has modded it at all. It's definately a fixer upper, but after looking at it, we started it up. The stock b18 (with no mods) sounded great when we turned the key, but then after 4 mintues of warming up in the cold air, it started to rev crazy. The tach was jumping up and down from 2k-5k rpm's. We gave it some gas, still continued. Held on the gas pushing the rpms up too 5k rpms and holding it for 10 seconds, still continued. Stuck our foot under the pedal and lifted it towards us, still continued. We asked if we could test drive it, but unfortunately the car wasn't inspected yet since it was from a pa auction. The dude said that the inspection should be done by friday and we could test drive it then.

So, what's your word on this. I really haven't messed around with B's before. Held more in the D's but what could it be. Would it be a vaccum hose or could it be an electric problem? My bud said that the gas light was on during start up so they didn't put a lot of gas in there. Would it be a sign of gas starvation? Whats up?

My map sensor was leaking vaccum and it did that crap..I pulled it off, and the engine died. Put it back on and it purred like a kitten, its done it a couple of times on the highway too, it started running way lean, far from home...I just popped the hood and pulled it, put it back on and twisted a little to get a good seal and shes purring again.