I asked before about Michelle's '96 Z71 (5.7 engine). It is hard to start after it has sat for a while, usually over 8 hours. It will just crank and crank and doesn't even attemp to start. It takes about 2 minutes to start it. Even after the engine is warm it doesn't start very well, sometimes having to crank 3 or 4 times for it to fire. The check engine light came on and it was a P1406 code, which the dealer said was EGR. He put a new AC Delco EGR valve on it ($150 ) and 14.8 miles later the check engine light came on again. It was suggested in my other post that I may have a vacuum leak. The engine has a plastic intake manifold. Twice it has happened that the throttle body stuck closed and it ran very rough; by depressing the gas pedal real hard it would free itself and run ok at higher rpm, but then ran bad again at idle. Could a vacuum leak in this area cause a hard start condition and cause a P1406 EGR code? The dealer is still trying to fix it, but I trust the opinion of my fellow ck5'ers more, and I would like to be educated on this so he doesn't feed me a line of BS. Thanks! I'm almost to the point that I would like to return the vehicle and get back our Explorer, but it's already been sold. Since we bought the truck: wipers quit working (I got this fixed at GMC under recall), the heater/AC circuit board went out, the starter quit working, and it's been to the shop for the hard start/engine light problem 4 times, going back for a fifth today!