Yanal

Hi there, I am not a mechanic but rather like to understand everything before i get deep into unnecessary repairs. My 2004 s600 suddenly received the N92/2 (ECI ignition module, left bank of cylinders) (P0300) with all the left bank cylinders 7,8,9,10,11,12 misfiring all together. I also have the N91 (ECI ignition system mains unit) (P0308) Stored. The car is very well kept and just passed 66k kilometers. My mechanic decided that it must be the left coil pack without even inspecting the voltage transformer and wants me to replace it without checking it. Problem is none of these parts are readily available in my country and it costs a fortune to ship and pay customs for them.

Any thoughts to consider before going through the painful coil pack replacement?

biker349

i'd go with voltage transforer is cheaper and seems to fit the symptoms. see if you can find one to switch before you buy.

Yanal

Thx Biker, I thought so as well. I will try the VT as you advised and hope it will work! Cheers!

Yanal

Hi guys, I visually checked the voltage transformer and I guess it is not the problem. Looks like I'll have to consider the left coil pack. The entire left bank is still misfiring all the time with the smell of gas all around the place. I am not driving it even to the tech shop until I know what's wrong. However

, when I removed the top plate I noticed a tiny hose broken! I am posting its pic here and hope if anyone can tell me what is it for and would it affect the misfiring issue! Thx for your help!

Investmentguru

My 04 V12TT is having the exact symptoms as your car. Misfires on 1-6, n92/1, and N91 codes showing, and the small plastic hose you pointed out is also broken on mine.

I also opened my transformer and everything looks good.

Did you ever figure out what was causing your misfires, and did you ever fix the small plastic hose?

Investmentguru

My 04 V12TT is having the exact symptoms as your car. Misfires on 1-6, n92/1, and N91 codes showing, and the small plastic hose you pointed out is also broken on mine.

I also opened my transformer and everything looks good.

Did you ever figure out what was causing your misfires, and did you ever fix the small plastic hose?

CL650BHP

Hi,

Have you changed the spark plugs?

if no and you have any doubt on when they were changed get them changed.

CL650BHP

Replace the voltage transformer which is on top of the engine with a NEW one or one that you know is good.

if this does not clear the problem then change both coil packs.


Alex

slonar21

You can get a loaner VT from http://www.v12icpack.com/ I went this route this summer, everything went smoothly, I recomend

CL650BHP

I just bought a voltage transformer and two coil packs from Clark Rupp at V12 coil pack.

Have changed spark plugs so the car is running amazing especially after a remap at DMS In Southampton.

Averaging 19 MPG after remap over last 1000 miles.

Alex

Investmentguru

Thanks for the advice. I don't think the plugs have ever been changed, although I do still average 21+ MPG on mostly highway roads; car has 80K miles.

Just bought the coil packs and 24 NGK OEM spark plugs. Tried the VT, but it wasn't the issue.