I bought an 86 4runner, ran great for one day and now sounds horrible and dies at an idle. Suggestions?

I expected something was wrong with it because it only cost $800 and it is a very nice rig, but then I test drove it for 30 miles and it ran great so I hopped on the freeway and took it the 40 miles home and got off on my exit and it died and has been acting and sounding weird every since. Always dies at Idle. This is my first Toyota and I do not know very much about them and would very much so appreciate the help. the cylinders all have 150 lbs and all the plugs are still firing. it's the 22R 4 cyl fuel injected. Perhaps an injector?