I just bought a 94 gmc sierra 1500 turbo diesel 4x4 and it runs great when it starts. If you plug it in 1-2 hours before you try to start it then it will start right up and be good all day. However if you dont plug it in at night the next morning it wont want to start. Batteries were replaced about a year ago. The guy i bought it from took it to the local diesel repair shop and they said it was the diesel injection pump, however it will run great all day with no issues after it gets started in the morning. Im looking for any options to look into before spending $1000+ on a new diesel injector pump. Any advice is appreciated