Have a 03 blazer ran great one day then like **** the next. I ran a computer check in it to find cylinder 1 misfire. Changed the ignition could and spark plugs Noticed oil on old plugs as well after changing these it ran worst!! Now I'm getting a multi misfire code. So I went back thru everything I did and cleaned around plugs with cleaner also cleaning the throttle body resetting pcm and disconnected battery for awhile to still have multi misfire now loss communication to drivetrain module??..help anyone?? Suggestions??. Thanks in advance.