Bosch Platinum 2- Bad Idea? - PeachParts Mercedes-Benz Forum

GradyService · #1 02-11-2007, 11:43 AM

After reading some of the threads on this site, I have been led to the (I hope faulty) conclusion that, 1. The only kind of plugs that a MB will run well on are copper non-resistors; 2. Definently they wont run well on the Platinum 2 Bosch's. Okay, well, before I knew better (last year), when I realized that the 560 needed plugs, I installed a new set of Bosch Platinum 2's

. The car seems to run okay, its better than the carbon soaked Bosch Supers that were in it before, but the car is a little noisy at idle (150k miles), and I was wondering, do I need to go out and buy a set of Bosch Supers (or Copper NGK's) so it will run like a MB ought? P.S. I liked NGK, and planned on going with them in the first place, but none of the local parts stores had them in stock

.
Thanks, and God Bless,
Dave.

MJM · #2 02-11-2007, 11:59 AM

Dave,

The Beru 14-9-DU would be a good choice for the 560 motor.

To this point I have not heard anyone say that the Bosch Platinum plug is a grand idea for the W126.

For what it's worth.

GradyService · #3 02-11-2007, 12:13 PM

Well, the part I really hate is, I only have 7k miles on the platinums. And, I would have to order the Berus online, because at most of the local parts stores, they go, Be-who's

. Anyway, what I am thinking is just run the platinums until the next scheduled plug change (158k miles), would that cause any trouble (I hate wasting a 50.00 set of plugs).
Thanks, and God Bless,
Dave.

MJM · #4 02-11-2007, 12:32 PM

Dave,

The Mercedes service documentation says using resistor style plugs can cause damage to your ignition equipment, with that in mind I've always gone out of my way to source correct plugs.

You could use one of the offerings from Champion or NGK.

Matthew

GradyService · #5 02-11-2007, 12:42 PM

I suppose that settles it then. I will find some correct plugs on monday. Is there a visual check for a resistor or non-resistor plug?
Thanks, and God Bless,
Dave.

MJM · #6 02-11-2007, 01:10 PM

Dave,

That is a good question, as far as I know there is no visible indicator except the model number to indicate if it is a resister plug or not.

Best of luck finding the right plugs, buy extras!

Matthew

hk20000 · #7 02-11-2007, 01:15 PM

does that apply to M111 4 bangers?

I stuffed some NGK dual plat into that thing and it purrs like a kitten.....the Bosch copper that was on it before (with rusted out body and tread, btw, I would bet up to 10 dollars that they came factory 212,989km ago) caused misfire and made it run on 3 cylinders.

I don't know about you guys but when it comes to electricals and electronic I always go find the trusty Japanese for them.... They seem to just....work.

softconsult · #8 02-11-2007, 01:23 PM

The last post is illogical.

Thinks the plugs causing mis-firing could be original, therefore the copper core plug specified for the car is defective and decision to install plug that is not specified as correct.

Could it instead simply be that the plugs are worn out and should be replaced with more of the same. Does the impression that the Platinums are running fine mean that they are doing no harm to the ignition components as time goes on?

Steve

hk20000 · #9 02-11-2007, 01:34 PM

I don't know what you yapping on about because NGK has its platinum application specific for the C220. In fact they suggest that iridium will do the trick too. Mind you my plugs came off a toyota engine that I was about to sell so it probably wasn't even the right plugs for the benzo.

But if the Japanese have been preaching on Plat and Irid for the M111 and no one called foul yet maybe they are indeed the right plugs for the car?

and the awesome thing about NGK is I don't think any parts store is going to ask you "EN GEE WHAT?"

1995 MERCEDES-BENZ C220 2.2 L4 M111.961 FI
Standard BKR5ES .032
V-Power BKR5E .032
G-Power Platinum BKR5EGP .032
Iridium IX BKR5EI .032

Oxygen Sensor 25556 Upstream
Oxygen Sensor 25536 Downstream

MJM · #10 02-11-2007, 01:36 PM

I'm really out of my depth on the M111 motor. I would use the Benz specified plugs upon replacement however.

Matthew

Quote:

Originally Posted by hk20000

does that apply to M111 4 bangers?

I stuffed some NGK dual plat into that thing and it purrs like a kitten.....the Bosch copper that was on it before (with rusted out body and tread, btw, I would bet up to 10 dollars that they came factory 212,989km ago) caused misfire and made it run on 3 cylinders.

I don't know about you guys but when it comes to electricals and electronic I always go find the trusty Japanese for them.... They seem to just....work.

hk20000 · #11 02-11-2007, 01:42 PM

As for the 560SEL wow you luck out they have wire set for you too! I'd give them brabus wheel caps for a set of those!

1986 MERCEDES-BENZ 560SEL 5.6 V8 M117.968 FI
Standard BPR5ES 7734 .032
V-Power BPR5EY 1233 .032
G-Power Platinum BPR5EGP 7082 .032
Iridium IX BPR5EIX 6597 .032

Wire Set EUC053 54248

Oxygen Sensor 25514 Upstream

softconsult · #12 02-11-2007, 02:17 PM

Thread was about 560 engine, didn't catch that you switched engines. However, I wouldn't count on Sparkplug mfg. and vendor recommendations. If you go on a few parts websites, you will see Platinum resistor plugs offered for use in engines where the overwhelming forum recommendation is not to use them.

Personally, I would strictly go with what MB specifies.

I was just reacting to what you wrote relative to the old plugs. I like to yap when I read things that strike me as worthy of comment.

Steve

willjohn123 · #13 02-13-2007, 03:19 PM

I have a 94 E420 that had P-4s when I bought it. I switched to the copper bosches and it ran like crap and got much worse mpg. What ignition parts will they damage? How long before damage will occur? Which one do I pick: a bad running car that runs for a long time or a good running car that might break?

suginami · #14 02-13-2007, 06:38 PM

The reason why you must use non-resistor type copper core plugs is that all platinum plugs are resistor plugs.

Mercedes Benz has the resistance in the spark plug wire (or coil wire) boots, so if you are using platinum plugs, you are doubling the resistance, which is hurting your spark.

The following is an excerpt from Arthur Dalton:

But the real reason the Benz solid core /resistor end wire setup is hard to beat is that resistor wires ohms are by the FOOT. So, each wire will have a different resistance according to length.
Whereas , Benz solid core wire has trace ohm and length difference is of no concern.
By putting the resistors on the ends, all plugs
get equal voltage, equal resistance.
Plus , being solid wire [ actually stranded ] , they last as long as any copper wire will [ very long]

suginami · #15 02-13-2007, 06:39 PM

Here's a good post on the spark plug issue:

http://www.peachparts.com/shopforum/showthread.php?t=164278&highlight=resistance