Hi All,

Newbie to the MB world. I have a 2005 CL65 AMG that I purchased not too long ago. It has 14K miles on it and is pristine and (ran) flawlessly.

I purchased and installed a Speedriven ECU/TCU upgrade as wall as catless downpipes. Within 200 miles of driving the car, while cruising at about 40 MPH the car dropped cylinders 1 through 6 and went into what I believe is limp mode. I have misfire codes on 1 through 6 plus a P0140 code (position 2 02 sensor failure). I've had someone I greatly respect suggest it's a coil pack failure.

Has anyone experienced a 6 cylinder, no warning what so ever coil pack failure....especially on a car with such low mileage?

As a footnote I'd like to give a public "thank you" to Jo and Marcin at Speedriven. They've both gone and continue to go above and beyond what one would expect from a vendor in attempting to help me isolate the problem. Good guys!

Thank you all greatly for any input, insight and suggestions.

John

i have heard many members complain about blown coil packs after a tune. so your friends probably correct. outside shot it could be the ignition module, but under the circumstances of the tune probably not.

Yeah most people's modules fail after tune. Go to local oriellys and they will be able to order reboxed, updated OEM coils at a reduced price with lifetime warranty.

Biker349 and TwinTurboTim: Thanks for the input, greatly appreciated!

I did check with O'Rielly auto parts....great prices (comparatively) and a lifetime warranty. Unfortunately also "not available" :o(

Any other input on a good source for coil packs?

Thanks!

I found mine through Auto Zone...
Cheaper than O'Reilly's and also with a lifetime warranty

AutoZone for the coil packs (slightly different cost for each side, lifetime warranty) and ebay for the ignition module (still $750ish). DIYers don't really have a way to know if it's a coil pack or the module until one is replaced. If the problem persists, it was whatever you didn't change!

In my case it wasn't the coil pack after all, but at least now we know they're good for another decade and the ignition module is too.

It looks like these things fail due to age rather than mileage. I thought my brother's 2005 65 had low miles @ barely 40k -- yours is barely warmed up! He'll soon be doing the exact same mods you have, just to keep it interesting

so the problem was the ignition module?

Hi all and thank you for the input!

I thought I'd write a little update. A little background: I'm a mechanical engineer, own an engineering company, a machine shop and a fabrication shop. I enjoyed a successful long-term career in auto racing that I retired from in 2006. I'm a very competent and knowledgeable hands-on mechanic. However I'm quite green to the modern automotive electronic world so please pardon my current ignorance in this arena. In a year I'll know this car well.

That said:

When my car failed it did so without warning and it dropped an entire bank of cylinders. OBD codes were cylinder 1 through 6 and bank 1, position 2 02 sensor. Many people suggested it was a coil pack failure...some insisted. This didn't make sense to me as dropping a bank of 6 cylinders simultaneously, without warning...what are the odds?

I learned that the position 2 02 sensors have no effect on the tune or performance of the car. They simply monitor the cats. However I also learned they can short internally and cause a back feed. I took the position 2 02 sensors out of the electrical loop. No change.

Reluctantly and against my own better judgment I purchased a right side coil pack and installed it. (By the way the coil packs are no longer available through any of the private or franchise auto parts stores). No change

Also, as a footnote, this was all done with a cold engine thus eliminating the inter cooler pump as an issue.

Upon installing the new coil pack, connecting the battery (reset the ECU) and starting the car the issue was there instantly. None of the 6 cylinders in question ever fired at all. Codes were instantly recorded. Same codes as before, 1 through 6 misfire.

This made it obvious that something in the system is controlling the coil packs individually. In digging into this I learned that the ignition module in these cars, although it's one piece, houses two individual, independent modules. Therefore one module "could" fail and instantly and permanently shut down an entire coil pack.

My next step is to install a new ignition module. I'll post the results.

I certainly welcome and appreciate any input from you experienced CL owners out there.

Thank you!

PS: I have a pristine coil pack for sale! :o)

Hi Shardul,

Thanks for the link but when you get to the page to pay it comes back "no longer available". In calling the corporate hub and them contacting the manufacturer they were told no longer available and no plans for them to ever be available again. Same result with every discount chain auto parts entity.

Hello all,

Issue ended up being the module.

I’d like to give a huge “Thank You” to Marcin and Jo at Speedriven. Those boys went far and above the norm in assisting me with education and troubleshooting. It’s a rarity these days to engage vendors that genuinely take pride in personal integrity. Marcin and Jo have earned my utmost man-to-man respect.

Thanks as well to the individuals that invested some time to post, greatly appreciated.

John

Could someone post the module part number and the best places to purchase one.

I'm glad to hear you are headed in the right direction with getting your car running properly. Its too bad your tuner never mentioned to expect the coils and/or the ignition module to fail. I would consider hanging on to the new coil, if you notice that the coils on the car are of the older part number. This was a common failure on the cars with the older coils once a tune was installed. I went thru the same issue along with others. At the time my car was under warranty, and my indy shop followed MB's protocol for the same codes. First they want you to check/replace the plugs of the cylinders misfiring then the coil. After that, I got the car back and after a few hard pulls it was the same. Then they replaced the ignition module before replacing the opposite coil, shortly after. So an after market tune puts a lot more demand on the entire ignition system. The newer coils seem to hold up fine. I don't know if the ignition module was updated or the weakness in the original coils causes it to fail. Either way, I'd hang on to the new coil and check you part numbers for the coils on your car before getting rid of it. Good luck!

For future reference, there's a local company that rebuilds the ignition modules if needed. I asked them about doing the coils and he said they used to but the parts that fail are hard to get nowadays and as a result he can't always do it, but the transformer/module they can rebuild.

http://www.programainc.com/

They are the same guys who make the Rentech lowering module. I ordered one from them recently.