Vague 04 Grand Cherokee running issue

Forgive me in advance for being limited on info. I am looking at buying an 04 Grand Cherokee that is currently having issues. Seems to be cheap enough to be worth the headache.
The seller has described to me that it just lost power one day, died and now will start but will only run if you keep your foot on the throttle. Once you let off the gas it dies. It isn't showing any error codes.
Does that sound like anything relatively common in this year/model Jeep? Are there any obvious things to look at first? Clearly my negotiating power is in the unknown but I also don't want to drag something home with a spun bearing thinking it's just the battery!.. and yes, I have had one vehicle in the past with a spun bearing that made no noise, ran fine but wouldn't idle without extra throttle!
If anybody can just throw out some possibilities, I'd really appreciate the speculation. I'm very knowledgeable under the hood, but not very familiar with Jeeps and their "special" tricks.