I was a victim of Bosch marketing, and bought a set of Platinum2s only to find that my 1992 300TE didnt like them, especiallly on cold mornings. Since Bosch has been marketing these plugs as suitable for use in all these cars, even though they really are not the proper plug, I am going to return them.

They have a form you can submit to get a refund, attached. You can also go to boschusa.com if you have other plats.

Attached Files

platinum2_guarantee.pdf (7.7 KB, 228 views)

Yep. The only good thing about platinum plugs is long life. Their performance leave much to be desired. In my Datsun I use nothing but copper NGK plugs.

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'83 240D with 617.952 and 2.88
'01 VW Beetle TDI
'05 Jeep Liberty CRD
'89 Toyota 4x4, needs 2L-T
'78 280Z with L28ET - 12.86@110
Oil Burner Kartel #35

http://i16.photobucket.com/albums/b1...oD/bioclip.jpg

Pre-millenium MBs don't like them...my VW sure didn't either! Stick with the copper cores in the future...

...this topic comes up periodically in many threads, btw.

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2009 ML350 (106K) - Family vehicle
2001 CLK430 Cabriolet (80K) - Wife's car
2005 BMW 645CI (138K) - My daily driver
2016 Mustang (32K) - Daughter's car

Due to the expense of platinum the electrodes are made very thin. This makes a thin spark. The wider electrodes of the copper plugs make a nice fat spark. That's the difference.

Additionally the platinums have been known to break due to their brittleness, causing catastrophic engine problems.

Merry Christmas,

Copper plugs don't seem to have any downsides other than you have to change them more often? Why are platinum plugs so popular? Changing plugs is so simple and the plugs are so cheap.

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2016 Corvette Stingray 2LT
1969 280SE
2023 Ram 1500
2007 Tiara 3200

I haven't researched it thoroughly, but I believe the use of long life plugs is driven by the requirement for cars to meet pollution standards for 100K miles. Manufacturers must certify (presumably through some type of simulation testing) their cars still meet the relevant emissions standards after 100K miles of usage.

Either it's a requirement that plugs not be replaced, or the manufacturers (reasonably, in my opinion) know they can not expect consumers to replace the plugs. So in go the platinums so the vehicle can pass emissions durability testing.

Your average consumer doesn't read the owners manual, isn't aware of when the plugs are to be changed, and won't take any action until they can tell something is wrong with the car. Fortunately newer OBDII cars have misfire detection and will light up the MIL if the plugs are too far gone.

- JimY

Does anyone have any experience with the Platinum +4 plugs? They are the ones with the electrodes around the edge of the plug...I installed a set last month and have been pleased so far with them in my 1988 560SL....does anyone else have stories about these?

i installed a set in my 1990 300SE they have been in there over 1000 miles.
i have had easier starts more power and improved fuel economy. the +4 seems alot better than the plus 2
Ray
mercedessd@cox.net

As pointed out above, platinum plugs are used for their longevity ( supposedly 100 k miles ).
On some of the newer engines you, the consumer, may be paying a mechanic up to 2 hours to change a set of plugs.
This could mean the original owner of a vehicle, who may possibly change vehicles every 4-5 years, would never need a plug change.
Another selling feature of platinum plugs is their low voltage requirements which, in some cases may result in a weaker spark.
As for double, triple or quadruple ground electrodes, my car uses them ( OEM ), but in a copper version.

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2007 C 230 Sport.

Get +4 coppers and get the best of both worlds. Sold under the names Beru Ultra X and Bosch Super 4.
http://www.kingsborne.com/

Use the plug that was designed and installed originally in your motor. That means copper in all MB motors till the 112/113 motors. Those motors take a platinum plug and it isn't a plus4 or 3 or 2 or any of that cr*p.

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Steve Brotherton
Continental Imports
Gainesville FL
Bosch Master, ASE Master, L1
33 years MB technician

i agree with steve, the main reason i installed the +4's were because a lot of my customers were wantin the platinums installed. over the years i have seen several cars towed in with a no start and it was due to platinum or non OE plugs that were installed. initially i manly wanted to see what would happen, and how the car would perform. i still recommend Bosch supers where they are called for, and the platinums in their correct application.
Ray
mercedessd@cox.net

The issue is NOT platinum electrode versus conventional copper core nickel electrode!

IT'S THE RESISTOR!!!!!!!!!!!!!!!!!

OE Mercedes plugs from the era of our cars DO NOT USE SPARK PLUGS WITH EMI RESISTORS.

Installing ANY plug that has a conventional EMI resistor, which is the common type for most cars, and REGARLESS OF ELECTRODE DESIGN, can cause driveability and/or emission problems.

Stick with non-resistor plugs, which pretty much limits your choice to the Bosch Super line. Parts establishments that cater to Mercedes owners (like Fastlane) should have the correct non-resistor type spark plugs. Most of the chain part stores WILL NOT have them in stock, and they may not even be able to order them.

Buy the non-resistor Bosch Super plugs listed in the owners' manual like H9DC for M103 engines. Don't buy the HR9DC. It has an EMI resistor - the "R". Most resistor plugs have an "R" in the plug type nomenclature.

Duke

So Duke, if we use the 'R' type plug, we can change to cheaper plug wires?

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Regards

Warren

Currently 1965 220Sb, 2002 FORD Crown Vic Police Interceptor

Had 1965 220SEb, 1967 230S, 280SE 4.5, 300SE (W126), 420SEL

ENTER > = (HP RPN)

Not part of the in-crowd since 1952.

I have no idea. The OE ignition system is engineered with specific coil resistance, wire resistance, non-resistor spark plugs, and shielding (the metal boot covers that contact the head casting) to create a proper voltage wave form/spark characteristics while meeting EMI requirements.

Change one thing and you may have a problem Change two things and you'll probably definitely have a problem.

If you're a EE with experience in ignition systems, feel free to re-engineer the system. If not, I would recommend sticking with OE or OE equivalent components.

Duke