kaixdiego

Doing some research tonight looking to get spark plugs for the ML and noticed when cross referencing that all plugs recommended for both are always one heat range apart.
Varying brands however swap which one is colder or hotter...?

Couple examples of what I am talking about...
NGK (ML55 one step hotter), i.e:

• NGK IFR6D-10 C55

• NGK IFR5D10 ML55

These NGK number however were cross referenced from two Bosch plug numbers, FR8DPP33+ (ML55) and FR7KPP33U+ (C55), both of which again show one range difference but,
this time oppositely, one step hotter for the C55...

What am I missing here? Or can some explain to why the difference in OE recommendation, Are they interchangeable?
I know the motors have slight differences but with both being 55's of the same era this confuses me a bit.

Any clarification appreciated!

cm60k

Early 98-00 (M113) ECU/MSG "ME2.0/2.0.1" uses little bit differ sparking angle than late (M113) ECU/MSG "ME2.8/2.8.1",,

never mine, you can use both of them with any "M111/M112/M113"..

-;-ZAYED-;-

kaixdiego

Any benefit you think between one versus the other?

cm60k

The benefits with better "Copper core center Electrode" & "Iridium ground Electrode",,

IMO; "Bosch IR Fusion 4504" & "NGK IFR6D10" are the best plugs..

-;-ZAYED-;-

kaixdiego

Would running the same heat range (6 NGK's) be okay for both motors?

cm60k

Do you mean "C55/ML55"..?

-;-ZAYED-;-

kaixdiego

yes, since all the plugs I looked at are recommended one heat range apart. Would I be okay running the same heat range specified for the C55 for both C55/ML55?

My theory is maybe they figured out a different heat range worked better as the engine got near the end of production, thus maybe running the same heat range for the ML55 would help it a bit. Also makes things easier ordering bulk of the same plug...

cm60k

Yeah sure, it will be okay to run one heat range colder for both..

-;-ZAYED-;-

kaixdiego

Thank you ZAYED! I'm going to be a bit of a guinea pig and test out the standard plugs from NGK, either 5553 or V-power 2756.

kaixdiego

ZAYED, any thoughts on running the NGK 5553? FCPeuro offers them and I picked them up, planning on testing them out. I know longevity wise they won't last as long but any negatives performance wise? Or ill affects on coil packs? I plan on doing a video series on install and update reviews.

arsupisemnet

Different ECU maps most likely

Ducatic230

Figured it was because of the heavier load on the ML55. Ecu would have some what of a different configuration on spark and timing.

kaixdiego

Good insight, I will test them and update with results. Videos for the install/updates will be on my YouTube channel as well.

cm60k

I'm certainly sure, All M113 (5.4L) with ECU "ME2.0", have the same "E-prom/file"..!!,,

if any differs between them, pls. chime in..

-;-ZAYED-;-

kaixdiego

That's what I assumed as well, they both have the same engine control system reports when using my scan tool however variances in canbus modules etc. Thx Zayed, will do!

cm60k

kaixdiego

Follow up:

I installed the ngk bkr6es-11 standard plugs in the c55 today, no changes in performance or any parameters thus far.

will follow up with more info as mileage increases.

Plan to install bkr5es-11 for Ml55 soon also. YouTube videos on both will be posted to my channel.

cheers