barry armitage

I want to thank you all for helping me in a solution for a problem with my 2001 CLS. It flashed the check engine light as I was on a long up hill highway and started missing badly. The code showing was P1399 with multiple engine misfires. The engine smoothed out during acceleration but at lo rpm "chugged". Idle also was at a lower rpm. After reading here for all the possible solutions, new ERG valve and channel cleaning. Checking the coils, gas injector cleaner. I found it had one bad spark plug. The center front plug looked good and would spark well outside the engine but was bad. Found it as I was pulling the socket connections from each coil to check them. I replaced it only and the car runs great again. Funny that one plug caused so much problem. I hope reading this helps others.