I have a 1993 full size blazer with a 5.7L motor. I sprayed throttle body cleaner into the throttle body. After letting it set, I fired up the truck. It is now idling at about 1800rpm and drops to 1100 rpm when I put in drive. Previously it ran about 900 rpm in park and 400rpm when in drive. I just changed the egr valve at the same time. It runs good. Just idling extremely high. Let me know if anyone has a suggestion