I HAVE A 1996 MERC420CL V8 AND WHEN PUT ON THE DIAGNOSTIC tester it shows a misfire on two cylinders .the misfires are on cyl 2 on one bank and cyl8 on the other bank ,the problem is the tester does not say what is causing the misfire so if any one had a similar fault please tell me what cured it. I HAVE DONE A COMPRESSION TEST and all the cylinders are equal so im thinking a fuel or ignition problem HELP HELP!!!!!!!!