BAD IC pump? check my test please
oh and I knew I was right about that shield being wrong, here look that shield is there to keep the hot intercooler pipe away. If anything the shield you designed might have the opposite effect and trap heat in
Last edited by SL65MONSTA; Feb 20, 2016 at 12:16 PM.
Short version: The circuit boards come out easily if you disconnect the coil wires and remove the torx screws. Having said that, there's not much point. You get to find out for yourself that the coil pack chassis is actually quite robust, but that's about it.
To replace a coil you need to remove the three small wire/foil connections. The connections appear to be welded or brazed, and are quote robust, but I found they're best removed by twisting them off with point-nose pliers. Twist them about the axis of the coil pin.
Yes, the coil pack might be good. Misfires are often caused by bad plugs, and people often change both (because it makes sense) to fix the problem. Only use NGK IFR6Q-G or Bosch FR7KI332S.
Identifying a bad coil is difficult. I couldn't find any electrical measurements that worked (and I'm an EE graduate). The only method that worked for me was visual inspection. This is what some of my bad coils looked like:

Sorry about the picture. The failure mode seems to be overheating within the coil, half-way up and close to the earth tag. Many of my coils showed varying degrees of overheating once I took the metal cylinders off (surprisingly difficult). The overheating causes the insulator to expand and split the cylinder along its welded seam. Some times the split can be very narrow, but its often the only indication of a fault. The coil still measures about 0.3 ohm on each leg.
Nick
The Best of Mercedes & AMG
Moreover, at the moment there is no use importing an item that might not be the problem I have , was hoping to do IGN test, get Eurocharged to check my data log, and test my coils, to make sure I am definetely not just throwing money away
Nick
Last edited by Welwynnick; Feb 22, 2016 at 03:40 PM.
It doesn't look like there is any way to measure the primary coil resistance externally. It looks to me like all the power pack (in the center of the engine) does is supplies 180V to the ignition drivers within each coil pack, and 23V for the ion current sensing, as well as battery voltage and ground. The remaining wires all connect to the main engine computer. Two channels of ion current signal wires, one ground wire for those, the 6 trigger wires for the coils, and two mystery wires labeled "ignition offset" and "ignition change" presumably for timing control or something.
Nick
Last edited by trabots; Jan 3, 2017 at 10:17 PM. Reason: clarification
I'm going to replace the driver side plugs soon, but when I replaced my failing passenger side coil pack, I noticed one of the seams had split. Since the entire pack was being replaced, I didn't think much of it.
Now the driver's side coil pack on my S65 is still fine with no misfires, but if I pull it out and the cylinders have split, can I still reuse the coil pack after replacing the plugs?
A split cylinder is a pretty bad sign. Coils will misfire and still have intact cylinders, so splits are pretty solid indicator of a burnt coil. But if it's that, or not being able to drive the car at all, then you can re-fit.
Replacing individual coils is DIY-feasible, but not easy. Getting the plastic covers off is difficult, it takes a lot of care and patience.
Nick
A split cylinder is a pretty bad sign. Coils will misfire and still have intact cylinders, so splits are pretty solid indicator of a burnt coil. But if it's that, or not being able to drive the car at all, then you can re-fit.
Replacing individual coils is DIY-feasible, but not easy. Getting the plastic covers off is difficult, it takes a lot of care and patience.
Nick
Would I be able to solder the cylinder back together using led solder?
The split cylinder isn't the problem itself - it's the over-heated coil inside.
Nick










