Happens to the best of them. Cylinder 7-12 misfire
Thread Starter
Junior Member
Joined: Sep 2021
Posts: 71
Likes: 9
2009 S600
Happens to the best of them. Cylinder 7-12 misfire
Now I know that this issues happens to all of the v12s. I'm looking into if it's the voltage regulator or the ignition coil. I have the voltage regulator taken apart and i've seen pictures of bad ones. I don't notice anything out of the ordinary or jumping out at me. It is always as obvious as an exploded cap or diode? Or is it one of those things where you just have to buy both because you can never tell lol.
Super Member
Joined: Dec 2018
Posts: 857
Likes: 501
From: Washington, DC
2007 S600, 2007 Chrysler 300 SRT8, 2000 C5 Corvette, 2017 Mustang GT, 2023 300C, and a 2019 Lincoln
Usually when it is all misfires on one bank, it is the Voltage Transformer. You might contact Clark Rupp at www.v12icpacks,com and purchase a rental VT and a rental coil pack on that side that is misfiring. He has a program where you can rent and test, and return anything not needed. I have both his coil packs and his VT and have been very happy with his products for about five years. Mercedes says these items are maintenance parts and need to be replaced at 45K miles and then again at 90K miles. How many miles do you have on the V12?
Thread Starter
Junior Member
Joined: Sep 2021
Posts: 71
Likes: 9
2009 S600
Usually when it is all misfires on one bank, it is the Voltage Transformer. You might contact Clark Rupp at www.v12icpacks,com and purchase a rental VT and a rental coil pack on that side that is misfiring. He has a program where you can rent and test, and return anything not needed. I have both his coil packs and his VT and have been very happy with his products for about five years. Mercedes says these items are maintenance parts and need to be replaced at 45K miles and then again at 90K miles. How many miles do you have on the V12?
Super Member
Joined: Dec 2018
Posts: 857
Likes: 501
From: Washington, DC
2007 S600, 2007 Chrysler 300 SRT8, 2000 C5 Corvette, 2017 Mustang GT, 2023 300C, and a 2019 Lincoln
If your coil packs and voltage transformer are at 130K miles and have not been changed, you are overdue. These are considered maintenance items by Mercedes and need to be replaced typically at 45K miles and 90K miles although many smart people think it is age (10+ years) and not mileage that causes the failures.
The correct URL for Clark Rupp's replacement upgraded products is v12icpack.com. I have incorrectly added an extra s to the URL on many of my posts.
The correct URL for Clark Rupp's replacement upgraded products is v12icpack.com. I have incorrectly added an extra s to the URL on many of my posts.
