my cousins 96 auto gst is doing some wierd things. he is on his fourth engine =(, i beleive the ecu has been modded because the rev limiter is gone. also his transmission will go into gear sometimes and sometimes it wont. when it does go into gear it it usually works fine but sometimes it feels as if it is trying to go to the next gear but wont go. i dont think its the transmission because i have been told there are 2 or 3 cases hooked up to the tranny that could be causing this as well. any help or suggestions would be great thanks!

also what would this car sell for? it has a body kit and spoiler a carbon fiber hood(its a little cracked) and he had a bigger turbo put on but he doestn no which one. thanks!