What does the fuel smell like in a GMC Sierra 1500?
What does the fuel smell like in a GMC Sierra 1500? If so pull the air filter off and sniff the throttle body for a fuel smell. If the diaphragm has ruptured it will literally be like putting a hose with fuel into the intake and running it full. What was the problem with my GMC Sierra 1500? Did have one cracked vacume line from the throttle body to the purge solenoid, also replaced. Seems to have plenty of vacume through out the system. Removed and inspected the egr valve, no excessive carbon build up and appears to be working...