88 b2200 revs like crazy

Hi guys, I am wondering if anyone can help me. My truck recently started having trouble idling and loss of power under load. It also started using more gas than usual. One day it blew a fireball out of the exhaust and sputtered out and died, I managed to get it running but worse than before. Rough idle and hard to start. I suspected fuel pump, just now I put a new one in plus the lines and a new set of plugs for the hell of it. The pump is working and there is gas in the float bowl, filter is also new. So now it idles OK, but as soon as I even touch the throttle it revs up to the moon and won't go back down, no matter what the idle screw is set at. The vacuum lines are all intact as well and I've replaced a few suspect ones here and there. It's a 1988 2.2ltr 5 speed carbed. Any help would be greatly appreciated

You might get a can of carb cleaner with a pinpoint nozzle and carefully spray around different parts of the places where things connect to each other, like the intake manifold to the head, or the carb where it connects to the intake manifold. Maybe a chunk of gasket broke loose and created this issue and you would eliminate this as a possibility with the testing. The other thing that comes to mind is that maybe the throttle return spring has broken but that doesn't seem likely since it sounds like you can shut the engine off and re-start the engine and then it idles. The return spring is behind the carb on the firewall side of the carb.

You think it could be getting air where it shouldn't be? That's an idea worth looking into. Also do you think it could be a sticky float? I've been up all night trying to research this and haven't come across a whole lot. Thanks for the reply

The float likely wouldn't be the problem. You have described a few symptoms so you are probably going to have to hunt them down one at a time. Rough idle is a maybe vacuum leak. How many miles are on your engine? You will probably have to pull the air cleaner loose from the carb to check things out.

I've pulled the air cleaner off multiple times and hunted around. I did find that one of the vacuum plugs on the intake had come off. I put a timing light on it today as was able to get it running good and idling but my original problem has come back. The power loss under load, going uphill it wants to bog out and die unless I put the clutch in a rev it a bit