hello to all, my dad has a 95 z71 that set up for 2 years. TBI with 5.7 engine and standard trans. To get it running again a new fuel pump was installed and fuel lines cleaned. Also purchased an entire throttle body off eBay that was rebuilt. The problem is that when you drive on rough dirt roads or any bumpy terrain the truck acts like it's not getting fuel?? It stalls and shuts down, you then can wait a minute and restart and it's good. I checked the tank and there is no trash. Thanks for any insight