Well I know its not a pontiac but I thought I'd throw it out to you guys here on the Bonneville forum. I have a 1985 Cutlass Supreme with a 231 V6. It was my first car over 10 years ago and we've been through alot. I have had this car in shows but sold it to my father for money for my first home. He didn't do anything with it for about two years and has now given it back to me. I had to replace a brake line and fuel line and was able to drive to my home. Now it seems to have a new problem. The car starts and idles fairly well although I notice some surging. When I put it into gear it stalls out. If I manage to get it into gear by nursing the throttle it stalls as soon as I press the brake. It also managed to drain a new battery after only a few weeks of sitting. Maybe just a weak battery but could be some kind of ignition problem I'm not sure. To make a long story shorter I want to sell the car but I need to get it to idle. I don't want to spend a ton of time with trying to figure out what the problem is. I'm thinking it could be a vacuum leak. A few of the lines have small cracks in them. How much of a leak if any would it take to cause a stall? It'* kind of hard to part with it. The car has never seen a winter and has all original paint (though faded on roof, hood and trunk). Engine was rebuilt a few thousand miles ago and the car only has 78,000 on it. I can't help thinking what it was and what it is now, though not bad at all, it'* just not the same and would take more than I'm willing to give.
Any help you can give would be greatly appreciated. Oh and if anyone is interested in buying it make me a decent offer.

Those old vacum lines need to be looked at, you have a leak. Replace any cracked or worn vacum lines, sitting around without proper storage can cause the lines to dry out.
A good tune up wouldnt hurt either if your trying to selll it?

i had an 82 cutlass supreme 231. i loved that thing to death.

check those vacuum lines first and foremost, don't be afraid to replace every single one you have.

i know mine broke something new about every 2 weeks or so, and it was always something different

i miss those days, to a degree...

hmmm... haven't dealt with a carb'd car in a while. not sure.

have you checked compression on your cylinders yet? might just be worn out after all this time...

Well here'* a bit of an update. I checked all the vacum lines I could find. One of the lines that went to a valve that connected to the charcoal canister had a few small cracks. I replaced that but still same problem. I ran it for quite a while and with it warmed up it ran at around 1000 rpm at low idle and surged up and down a few hundred rpms. I was able to put it in gear and no stall.I know that is a high idle but when I brought it over to my house I had to increase the idle with the idle screw so that it wouldn't stall. I didn't include that I had increased the idle in my first post. I then decided to try and lower the idle to around 700rpm and sat in the car to watch the tach and listen to the engine. It will idle fairly smoothly right around 700rpm. I then blipped the throttle to around 1300 or so and it would stay there. Almost where it should be since the idle screw is still increased just not as much as it was. It would surge just slightly but stay right around 1100 to 1200rpm. If I tap the gas again it would settle back down to 700. Seems to me like the carb has some kind of issue. Does this seem to point to anything or just nothing. I'm gonna pick up some carb cleaner tomorrow and see if I can loosen something up Let me know what you guys think.

clean up that carb, and if you can, check the compression. Poor man'* compression check - put a ratchet on the crank and try to turn it over by hand. if it'* difficult, you're prolly good to go

however, if it doesn't take too much to crank it over, or you can't feel too much difference throughout the rotation, you've got some problems. when my shadow done died from bad compression (that car has died many times), it would do about the same thing. you could get it idling somewhat (it was pretty bad though), but putting it into gear, it would die almost every time if I didn't keep on the gas. Turns out the compression was so low that the force of the clutch packs putting the tranny into gear was enough to stop the cylinders dead in their tracks...

Thanks for the ideas. I don't think it'* a compression issue but it may be. It runs very well when you rev it up and down to 2500 rpm. Nice and smooth. I did in fact drive the car to my house about 2 months ago and after filling it up with gas I was surprised how well it drove. It shifted well and had plenty of power. It only has about 7k on the engine and was built by a reputable shop. So so far its all just an idle problem. Idle has been brought up from what it always ran at. Set it at 1000 rpm and it will not stall when shifted into gear. Bring it down to 700rpm and it will stall. Let it idle at 700rpm, tap the gas and it will hover around 1100rpm until gas is tapped again. It will then return to 700. One other thing I observed is that with car in park and idling if I press brakes rapeatedly about 3 or 4 times it will bring RPM down a few 100rpm and stay there until I press gas and then return to 700 again. Sounds like a vacum problem to me again. Let me know what you think.