2004 gmc envoy_slt
Good day all new to trailvoy and would like to say hello . Got a 2004 envoy just got it bout a month ago been working out some bugs replaced the oil press switch so far so good . Am planing a few mods like maxcam 2 lift kit and maybe a body lift . Has enyone ever noticed a occasional chirp sounds think it may be comming from the engine bay sometimes on decel or light pedal modulations could it be the vvt actuation system ?? How does the variable valve timming work ?