My 2000 Silverado 5.3 is very hard to start when it is warmed up. When it is cold it will start right up. Also, if left to idle for 15 minutes or so, it will bring on the Check Engine light. This should be no problem except I cannot read the codes from the OBDII. It only works for the inspection stations not for the normal obdii readers. I have been checking for a possible vacuum leak somewhere in the line to the transmission or vapor cannister. Is there something that I can do to fix the code output connection or just get a new computer?