Engine Performance problem
1997 GMC Jimmy 4 cyl Four Wheel Drive Automatic 97,000 miles

gave a complete tuneup,wires,  plugs,cap.rotor.fuel filter .service engine soon light came on and was check it read,running rich (bank 2) and i replaced #6cylinder fuel injector and the engine runs better. but in the morning the truck starts and runs fine.After a while driving it and the engine is heated up i will shut it off.then go into a store for a few minutes and come back out and it takes several cranks before it starts when its warm.any idea whats the problem? thanks mike..............

Hi:

Have you had the computer checked for trouble codes? If not, have it done. Most nationally recognized part stores will do it for free. Also, have you had the fuel pump pressure checked? If no, have it done and let me know what you find.
Joe