I have a 99 tahoe with 5.7. I just replace the fuel regulator and the gasket for the top half of the plenum. Now it idles at 2000 and has super high vacuum. If I pull the intake hose off the tb it idles down. The vac is hard enough if ya pull the pcv valve out of the valve cover it will suck it right back in. Any input im at a loss.
