Well I turned the screw under the seat and it doesn't change anything for me. My truck idles at 1500 cold or hot. and about 1600 with the air on. I can turn the screw to faster idle and it comes down just a hair, But the engine light will flash 1 then 2 then 3 then 4 then 5 times. And will not go off. It keeps doing this. The truck has 122,000 miles on it and it has been sitting outside parked for 2 years. It runs great but it also idles high. Any help would be appreciated.