ok. so i have a 1988 2.3l mustang. i finally got it to turn over after i found out that the battery was completely dead. but now i cant get it to fire effeciently. i have to keep my foot on the gas to keep it running. in other words, keep the throttle completely open. once i take my foot off the gas, it dies. note that i already installed a new throttle position sensor. i wanted to know what other things can be causing this to happen?