I recently bought a 85 4Runner with 22re and at the time it ran great but when I was on my way home from the store today it started losing power and then I got home and it started idling low and rough. When I got home and let it idle I would need to have my foot on throttle just to keep it from dying. Anyone know what’s wrong?

 

Could be a million things, I know you are probably frustrated and want a quick answer, but nobody here on the forum can see your engine bay, we don't know the history of the truck and we don't know what you've tried.

If this is sudden, as in, things were running great, and then all of sudden the truck is not running great, I'd check the obvious things, like are all the plug wires connected. I had one pop off once while driving and the truck ran rough suddenly. Also, check for vacuum leaks. You can look for obvious ones, like a hose disconnected or broken. Also look carefully at the air intake tube from the AFM to the throttle body, if that has a crack in it, that could make it run rough.

There is also a potential that the idle adjustment screw has worked its way loose. There is an o-ring on it that becomes brittle over time. This could be a vac leak if not sealed properly.

There are a tons more things that could be wrong and people on this forum have tons of info to share with you to get to the answer, but I think you have to do some basic troubleshooting and give us more info. You bought the truck recently, did you do any under-hood maintenance to it? Does it matter if the engine is hot or cold?