I have a 1992 full size Blazer with a stock 350 TBI. It has had a vacuum problem that I could not find for some time. The truck was idling high (1200-1500rpm). Changed the plugs,wires,cap,rotor,coil, and the fuel pressure regulator. Finally found the leak- the egr solenoid would not hold vacuum. I replaced the solenoid and the idle dropped down to 600-700 rmp but it idled very rough. It almost would die when I would stop at a light. I tried blocking of the vacuum to the solenoid and to the egr. Result was it ran some what better, still rough idle, but the smell of gas is every where and I am getting black smoke. To eliminate an egr leak, I replaced the egr and gasket, cleaned the passage way as well. The truck now idles at 600 rpm, but not real smooth as it should, and the gas smell is still there and the black smoke is as well. I cleaned the IAC as well. The truck did not smell or run rich before I fixed the vacuum leak. Could the fuel pressure regulator have ruptured or the IAC is just bad????? I am at a loss and need this truck to run right. Thank you
Sep 9, 2010 at 6:53 AM