sr20 black top wont start

[ATmintz]

my battery has not been able to hold a charge for about a week, but its like 6 years old and a lawnmower battery so not surprised, but other day went out and when i jumped it it turned over but then wouldn't stay alive, it would sputter at 300 rpms then shoot up to like 3500, and will keep doing this.. i tryed to give it gas and wont go past 4500. i have no idea what happened, it drove perfectly the day before and i didnt notice anything different... its getting towed to a shop shortly but if anyone has had this happen and has any idea what it could be please help

[mRodiek]

Check your MAF