w216 CL65 - Location of MAP and CPS
I don't have a tune and I changed all the spark plugs. I don't think it's the spark plugs because the misfiring only occurs in cylinders 1-6 on WOT.
I suspect it's something that is dedicated to the passenger side cylinders. I also suspect that I might have a clogged catalytic converter that is creating back pressure. But, figured I would try replacing the sensors first. I looked for any hoses that might have issues (disconnected, loose, leaks, etc.) but couldn't find any. There is what appears to be a sensor on the rear of the passenger intercooler that I was careful with when I changed the spark plugs. Does anyone know what this sensor does and if it could explain the misfires isolated to the passenger side cylinders?
Thanks for everyone's responses so far.
Hector
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I really don't think it's the spark plugs. Otherwise, cylinders 7-12 should be producing misfires. The misfires are only to cylinders 1-6, and only during WOT (wide open throttle).
The turbo engines use FR7KI332S, which have a plug gap of 0.7mm.
Lots of people get this wrong, including mechanics and retailers.
Nick




,,ZAYED,,
thanks


p.s. great info,but this is really a bummer.
if these can only be used on the naturally aspirated engines is there anybody who would like to buy my set of 24 unused and still boxed plugs?
That's not to say that fitting FR7KPP33U+ will definitely cause a misfire, or that fitting FR7KI332S will definitely make it go away, but it's a pretty worthwhile bet IMHO.
Unfortunately some of Bosch's own websites recommend the FR7KPP33U+ for the V12TT, hence the confusion. However, this one at least does point to the FR7KI332S
https://au.bosch-automotive-shop.com...keyNumber=3770
Mercedes manuals always specify NGK IFR 6Q-G with a gap of 0.7mm / 0.028", while the unblown engines all have plugs with 1.0mm gap. The FR7KPP33U+ has a pre-set gap of 1.0mm, and the FR7KI332S is 0.7mm.
Bosch also state that you shouldn't re-gap these plugs, as it weakens the electrodes, and it changes the geometry of the electrodes, which affects their life.
Regards, Nick
on a side note how do you set the i think it's called dyno mode where you can see your battery voltage, battery charging, etc. on the instrument cluster. i can't find the info although i've done it in the past. i believe it has something to do with settings on the climate control. any help is greatly appreciated. i hate it when i forget things and can't find the info.
thanks

Nick
Edit: Sorry if that seems a bit abrupt or arrogant, but for those who don't know me, this is what I've done with my silver V12TT over the last four years. The items in bold are my own new modifications or service / repair methods:
Engine:
Rebuilt turbos with engine in situ
Engine mounts in situ
Long coil pack heat shields
Synchronised waste-gates
Diverter valves
T-bolt clamps
Engine radiator
Engine fan
Coil pack
Transmission:
Transmission rebuild
Torque converter
Conductor plate
TCM Connector
Oil, filter & gasket
Transmission mount
Suspension:
Wide front wheels & tyres
Compression jointed ABC hoses
Fire sleeved ABC hoses
Uprated front strut bushes
Uprated steering bushes
Rear struts
ABC pump
ABC pipes
ABC accumulator
ABC Height sensor
Charge cooling:
Engine radiator
Engine cooling pump
Custom pump controller
Coolant temp sensor
Header tank
Charge Cooler Bleeders
Insulated Charge Coolers
Insulated IC pipes
Consumables:
Front tyres
Front discs
Front pads
Rear tyres
Rear pads
Rear shoes
Battery
Spark plugs
Speed sensors
Lambda sensors
Temperature sensors
Pressure sensor
Rain sensor
Lots & lots of O-rings
Windscreen seal
Raised rear seat cushion
To-do List:
Intake pipe heat shields
ABC water cooling
Large throttle body gasket
Android Head Unit
Fuel pump
Ignition switch
Rear discs
Last edited by Welwynnick; Aug 31, 2016 at 06:47 PM.
NGK 5648 IFR6Q-G Laser Iridium Plug
- Thread Size: 14mm
- Thread Pitch: 1.25mm
- Seat Type: Gasket
- Resistor: Yes
- Resistor Value: 1K Ohm
- Reach: 19mm (3/4")
- Hex Size: 5/8" (16mm)
- Terminal Type: Solid
- Overall Height: ISO
- Gap: .028" (0.7mm)
- Torque Specs: Cast Iron: 18-25.3 lb. ft. Aluminum: 18-21.6 lb. ft.
- Brand: NGK
- Heat Range: 6
- Longevity: 80-100k
Center electrode materia...lIr
Connection type....Non-detachable DIN/SAE head
Designation...Spark plug, Iridium
Diameter_center electrode....0,6 mm
Electrode gap....0,70 mm
Ground electrode material....NiY + Cu + Pt
Independent aftermarket part (IAM)....0242236571
Interfer. supp./burn-off res.....6 kOhm
Number_ground electrodes....1
Sealing seat....Flat
Spark position....4 mm
Thread diameter.... M14 mm
Thread length....19,0 mm
Thread pitch....1,25 mm
Tightening angle....90 °
Tightening torque....28 Nm
Type formula....FR 7 KI 332 S
Width across flats.... 16,0 mm
Last edited by Welwynnick; Aug 31, 2016 at 05:46 PM.
Anyway, at this point, this may be the least expensive thing to try in order to get the misfires to stop.
I would highly recommend to ONLY use the NGK-Spark-Plugs recommended by MB.
So you will have no trouble and even better you can say -it is not the spark Plug- if you have some misfiring (normal mileage of the plugs assumed).


That's a great result, and I hope it saves a few V12TT coil packs in future.
Well done,
Nick










