NRL

Lol, I"m not. Just trying to be extra careful the first time..

I'm sure it's easy.

mkhurley

You'll be surprised how easy, as I said earlier in this thread, they actually thought about having to work on this car when they built it, so things are relatively simple to do and even though they may be tight quarters, it's enough to allow you to work without removing the engine. Looking at the coil pack in the pics and how much room was available on the sides of the engine, I thought no way, but there was just enough.

Unlike my wifes old Grand Prix GTP, which required you to sacrifice your knuckles to the gods just to change the plugs.

NRL

As I work on it in the evenings,

Ordered the Spark Plugs on Amazon Prime:

NGK (5648) IFR6Q-G Laser Iridium Spark Plugs


Right Ignition Coil and Plugs on the way..
I'm only going to do one side first.

tqtrin3

Hello all,

I have 2004 SL600 with 40K miles,

1) at first the car start losing power from time to time but turn off the car and restart it again will take care of the problem, it will run normal.
2) sometime it will shut off the engine at the red light, but start the car again will also take care of the problem.
3) after a while, the check engine light up with ODB2 code P0300, P0307 through P0312, reset the code with ODB2 meter or disconnect battery for 5 minutes and reconnect will take care of the problem and the car will run normal.
4) after a few time, the ODB2 meter can not reset the code any more it say erase error.
5) every few days I start the car again, sometime the check engine go away and the car run normal for about 50 miles and the check engine and ODB2 code come back, car lost power.
6) replace both front and rear batteries, check engine and code go away, car run normal for anothe ~50 miles. check engine and ODB2 code come back car lost power.
7) bring the car to Mercedes dealer (south bay area ) california. they said it could be either the IGN. control module ($1124 parts and labor) or Coil Pack ($1963 parts & labor).
8) dealer recommended to replace the IGN control module first, if the misfire does not go away than replace the coil pack.

After read all the threats on this site I decided to replace the coil pack first by myself, with my brother help, he was a mechanic.

* can anyone please help with some thoughts/advices?
* can anyone please tell me where to buy or order the coil pack (dealer want ~$1500)
* is it the driver side coil pack for cylinders 7 through 12)
any help or advice are deeply appreciated.

thanks a millions in advance.

Tien

mkhurley

7 thru 12 is the drivers side correct, parts.com seems to have good prices, not sure if they'll carry the coil pack though.

I think your right going with the coilpack first, if the misfires were scattered I'd look to the control module first, but not one side.

Take your time, it's easy, there are threads on here that will help with removal.

NRL

In the end, I had the same symptoms as you got..
But it started out with it misfiring randomly only when I gunned it (4k rpm), then as time progressed, I got CEL's all to my Right Coil pack and a permanent limp mode.

I went for replacing the ignition transformer first since it was cheaper then the coil pack. The install was really easy, but it didn't fix anything, coil pack still was misfiring. So I went to the next step of removing the coil pack to see..

In my case, a small amount of oil that got in the spark plug hole of cylinder 1.
Or my coil pack with the older partno finally died.

If your going to do it yourself and decide to pull the coil pack:

You might be able to get away with just inspecting it by pulling the coil pack off and check your plugs for oil that fell into the coil plug cavity thru time.. follow the DIY with pictures that was posted on removal process; I found it searching this site.

The first thing you'll see after removing the coil pack then the spark plugs; on one or more plugs, a thin layer of oil on the red insulator boot and oil on the upper part of the spark plug..

Good time to clean the spark plug cavity holes and change all the plugs on one side.

Then you can decide if you want to buy a new coil with the updated partno that superceded the coil pack with the old partno. Coil Pack is about $1000.00 after shipping from parts.com. Get a new one, not refurbished.

Or you can put the original pack back in..but there is no way to test it really before you put it back in and try it unless your an electronic technician.
I would inspect the red insulator boots for burn marks and make sure they are not hard and brittle, etc.. and get new red insulator boots if you need them.


I'm at a point of putting mine all back together, spark plug #14 and counting.. it's pretty time consuming but if your careful and take your time, it's not hard, just tedious. Also, get a back brace support cuz it's hard on the back leaning over..

Hopefully it's going to purr like a kitten and and roar like a lion with net new with the tune..


Trust me, the dealer will never really clean your spark plug cavity holes the way you'd like them..spotless

abiazis

My 7- 12 cylinder driver side misfires/CEL were addressed as follows:

Replaced spark plugs that were fouled (all 24)/cracked map sensor - still had misfires immediately next day - $ 400 out of pocket - bad diagnosis

Replaced ignition module (voltage transformer)/intercooler air temp motor - still had misfires after 2,500 miles and 6 months later - $ 2,000 warranty

Coils always tested okay and catalytic converters were okay along with crank position sensor....... - $ 1,800 warranty

On the third time in the shop.......Mechanic saw an arching mark near cylinder 12 and a white powder substance on parts of coil - dried moisture ? - replaced the driver's side coil pack even though showed okay on MB Star tester..........issue solved for now.........picked up car last week.....

My misfires only happened under full throttle acceleration........no longer does that.........so replace the coil as planned and hopefully that will be the issue unless ignition module, etc. have issues............good luck)

Costly trial and error part replacement stuff for sure....

tqtrin3

Hello all,

Thanks all for the valuable advices, I will plan to do this this next weekend and will post back....

Hi NRL thanks for the advice, I will follow your suggestion and inspect the plugs and coil pack first before order from parts.com can you please point me to the DIY instruction with pics post?

Can someone please help and tell me if I need to buy any special tool to make the job easier?

thanks in advance.
Tien

NRL

https://mbworld.org/forums/m275-v12-...-pictures.html

NRL

I did it once without that special tool.. And the rest with that ingenious tool.
Its easier with the tool. Made by Hazet, Mercedes Part# 137589003300.
You need the base too 285589009400 which is used to leverage on the valve cylinder cover, and pivots the coil out a bit at a time..

Again not necessary, just makes it easier.

Good luck, I just got mine all back together, a new beast..

abiazis

Car still running good after a month.....hooray............

NRL

Yup, me too!

Enjoying the new revived beast!

To me, it hits 100 way faster..

abiazis

Much better when they are running right!!!!

What was your total cost to fix? Mine was about $ 3,000 with new plugs, map sensor, ignition module and ignition coil.......warranty covered coil and module work...

NRL

here are some pics of that tool I mentioned and some other pics







And a Video of me doing it one handed! (Just kidding, I practiced removing the coil like 4 times)

NRL

I bought the parts from parts.com, and the car is not under warranty (yes, I went for it not getting it, so far two years saving $500 per month for a rainy day, so far I'm ahead)

One Coil Pack ~1100 with shipping
Transformer ~620 with shipping (This was not needed in the end, but it was the first thing I tried, easy swap)
NGK Iridium Laser Spark plugs from rockauto ~9 bucks a piece x (24) = ~216
Official Mercedes Spark Plug removal Tool $35.00
Special Tool for Coil pack removal (Hazet, Mercedes Part# 137589003300, 285589009400) ~$250.00

I already owned a Star MBStar Diagnostic to clear the codes, run tests, and check it completely. $650.00

Labor $0

Overall it was a good intro to the gorgeous M275 engine.

Nervous Fun Factor and getting to know your AMG, Priceless...

cjcalo

Is the ignition control module the same thing as the ignition transformer?

abiazis

I believe it is the same.....

I have heard it referred to as:

Ignition control module
Ignition transformer
Voltage transformer - mercedes dealer info

NRL

It's easy to replace as a first easy and cheaper thing to do.. but if you still get codes after the swap, then it's something else.. coil pack.
here is some pics of it:
the Voltage Transfomer:

NRL

Ok guys,
Here some pics of what caused my misfire issue that eventually made my old coil pack (old part#) go haywire. I have no idea if that old coil pack I replaced out is any good any more by the way..

The first pic is what I found, a bit of old oil that made it from the oil filler (someone missed, and spilled a bit) and it flowed, as you can see, a straight shot into the spark plug cavity hole. There was a old oil trail that I cleaned up that lead all the way down to what you see. No new fresh oil was spotted.

Another theory is the the valve cylinder gasket is known to produce a leak after awhile, small tiny leak that eventually collects, so I torqued all the cylinder cover bolts to spec. I'll tear it down 6 months or next year and look for tiny, tiny leaks if this was the case and if needs it, will put in a new valve cylinder gasket which doesn't look to hard to do.

First Pic:


Second pic shows how the filler cap is directly above the spark plug hole:


Here is a pic of almost every cavity hole I cleaned out with a hemostat tool wrapped with paper towel and simple green.. clean as a whistle:

cjcalo

Don't quote me on this but I was talking to a mercedes mechanic that's very familiar with our v12s and he said that the transformer rarely needs to be changed and may never need to be because they hardly fail. He said that the misfires come from bad ignition coils 99.9% of the time and that if the transformer is bad that the car would likely not run at all. He said that most people don't really know if its the cause of the misfire but they replace it anyway just to rule it out since its easy and cheaper than the coils. He said that every time he's replaced only the transformer the customer soon brought the car back and replacing the coils fixed the problem.

abiazis

What you describe is what happened to me. Transformer replaced first, along with a motor for the intercooler, which fixed the misfiring for about a month. Replaced driver's side coil (cylinders 7-12) after misfiring returned and then okay now for the last 3 months.

Per this forum I understand that the coils have been upgraded since 2005/6 with a new part number and failures are not as prevalent in the later V-12s - 2007 ? on......

cjcalo

Yes there is a new part number for the coils which are supposed to be better than the old ones. From what I gather, the old coils generally last anywhere from around 40-60k miles before they start failing. Mine fit that bill my car has 53k. But I still believe that the tune accelerated its death. In hind sight I would have waited til the coils failed before doing a tune on the car.

cjcalo

I am about to order both coils for my car I went to parts.com and notice that they charge $250 for shipping to California? This seems very high to me is it their standard policy to charge this high for shipping?

abiazis

I would get on the phone and see if you can bargain since the cost is pretty stout.....

Or....have them ship to someone you might know in their locale (or potentially pick-up if possible) and have them reship them to you for less?

NRL

Is that $250 for each?

In early April I bought the right side coil from them for $936, plus $27.00 shipping and 2.00 handling. Still a good deal in my opinion in getting a new, real deal, in a mercedes box.


I think the website mentions that the shipping is just a quote and will be adjusted. You might want to call them to confirm.

Hopefully they didn't increase their prices since then..