This was my first car and I parked it many years ago and when I did it wouldn't rev over 4000 when in gear and wouldn't go over 45mph. When I parked it the dash lights only consisted of the gas light and the check engine. The other day I was pissing around and decided what the hell maybe I'll fix it. I jumped it took a few tries but it started up and ran pretty shitty at first. I let it run for a bit and it cleared up. So I took it around the yard and back the drive way and I still it wont go over 45mph it shifts gears but has nooo power. Any ideas? I did change the air intake temperature sensor and the only dash light on now is the gas light. I hooked up a code reader and no codes are showing.It sounds like its missing a bit but wouldn't that throw the check engine light?