hey y’all. so i already own an 01 gts that’s modified however someone on my street owns a gt that has a bunch of body panels i need. if i bought it tho i’d just swap panels and sell it for what i paid. however it doesn’t seem to run right. i’ve talked to him and heard it drive and it won’t go past 20 mph. i thought maybe limp mode or something like that but when he drives it it sounds almost like rod knock. however as soon as he stops the rod knock like sound goes away. anyone have any ideas why it would be doing this/if it’s an easy fix? i’ve done engine swaps and stuff of that sort but i’m more thinking price wise.