the best spark plugs for my 1994 C280 - Benzworld.org

aroppi · 01-20-2003, 04:25 AM

hi!! i'm aroppi from Hong Kong and i'm using a 1994 C280 with straight 6 engine. it's really a great car and my dad likes it very much also!!!
i'm going to change the spark plugs for it and wanna try other brands beside the original parts.
any suggestion?? Thanks!!!

Sergio · 01-20-2003, 10:02 AM

Use the same exact plugs that the car came with (BOSCH). Do not try the titanium; use copper plugs only.

aroppi · 01-20-2003, 10:26 AM

thanks for the reply!! but...
why?? how about those called iridium spark plugs??
seems that the iridium plugs are the "longest life" one!!!

Sergio · 01-21-2003, 10:56 AM

Modern MB engines can use titanium plugs. Older ones (don't remember how old but '94 qualifies as older) cannot. I can't remember why and I wish a had a logical explanation BUT someone with greater mechanical knowledge explained this to me and I corroborated it with MB service department. It's not worth risking damage to your engine.
As far as longer life, if you replace your plugs every 30-50K miles or so, that should be OK.
Last time I did, I paid $1.63 per plug and it took less than an hour (well worth the small investment).

Sergio · 01-21-2003, 11:01 AM

Modern MB engines can use titanium plugs. Older ones (don't remember how old but '94 qualifies as older) cannot. I can't remember why and I wish a had a logical explanation BUT someone with greater mechanical knowledge explained this to me and I corroborated it with MB service department. It's not worth risking damage to your engine.
As far as longer life, if you replace your plugs every 30-50K miles or so, that should be OK.
Last time I did, I paid $1.63 per plug and it took less than an hour (well worth the small investment).

aroppi · 01-22-2003, 04:44 AM

got it!!! thanks for your advise!!!

by the way, i found that my C280 has a kind of "floating" idling rpm when i slow down the speed from driving. say, from fast road to junction. once i slow it down by pressing the brake, the rpm will drop smoothly but once it reach the idling rpm, it starts to "float" +/- 300rpm!!!?

well, any idea about this??

suginami · 01-22-2003, 06:45 PM

Sounds like a vacum leak or a defective MAS sensor.

///S320 · 01-22-2003, 07:34 PM

I had this problem when i had a c280, had to change the spark plugs plus the ingnition coils.

aroppi · 01-22-2003, 08:05 PM

Once again, Thanks SO much for the replies!!!
well, let me say something more...

i found that once the idling rpm starts to "float", i press the gas pedal again, then the idling rpm will go up then stop for a second on @1000rpm then drop smoothly to the idling rpm. if not, the rpm will still "float".

by the way, what is MAS sensor??

P.S. i've changed the spark plugs to the original parts yesterday and i've changed the ingnition coils 6 months before.

timecop369 · 01-22-2003, 09:40 PM

I'm assuming MAS meter is the Air Mass Meter. I had to change that on my 1999 C280 to get the engine light to go off as the Oxygen sensor was detecting that my mixture was running lean.

The part is on www.bimmerzone.com for $196.26. Look in section of air intake. This is cheapest place you'll find it... trust me on that!

Good Luck,

timecop369