First I'd pull a plug wire and test for spark. Second, if its been sitting for 3 months, the gasoline could have started to break down, putting some fresh fuel in it may be enough to bring the octane back up to running level. However, 3 months is NOT that much time and gasoline doesn't break down that much in such a short time. As far as mileage? hehehehe I have a 90 with the 2.5 that I bought for $200.00 with 265k on it. It now has 315k and up till just the other day NEVER let me down. I live in Delaware and have on several occasions taken it to Pittsburgh and back (about 750 miles round trip) with ZERO problems and ZERO oil consumption. Mind you, the engine in this 300k plus beast only has about 150k on it. But hey, most 4 bangers at 150k are pretty close to wore out if they weren't cared for so I think this one's pretty darn good. So don't let mileage scare you IF you can get good, reliable intel on how well the upkeep was done during the 213k miles that are on YOUR prospective car.