its a car im tryin to decide if i wanna buy or not....1g2av7hxdl21

The VIN is a little short, I'm assuming your cutting off the seq. But there is still something wrong, I think your missing a digit. there is a V which is for formula but you have a DL at the end which would be an 83. there was no 83 formula. however the L could be the year, 1990, which did have the formula. but there was no D code engine. but you have a as the 4th digit which was true for 82-84 model years. if its a 90 it should have F in the 4th digit.

well i wrote the vin down from the car itself

Yeah, there's definitely something missing with that VIN.

L = Van Nuys
D = 1983
H = 305 ci V8 LG4
you have a V but i think its gonna be a W
W = Trans Am
A = Manual belts
2 = Pontiac
G = General Motors
1 = USA

that makes sence, if we assume the V is suppose to be a w then the digit missing is a 8 after the W which would fit with the 7 after that. Like 1G2AW87HXDL21????

ok i see...how long is the vin supposed to b when its posted?

The VIN is 17 digits, the first 11 discribe the car, the last 6 are the sequence number.