vhouc

Hello, I have reached 100K and replacing my spark plugs Bosch +4 Electrode, Do I need to replace the Spark Plug Wires as well? Can I just re-use my old ones?

samaritrey

I would just buy OEM Bosch plugs not some new fancy one.

kirax2

i just replaced spark plug with NGK, i don't really think our car has wire but i could be wrong.

samaritrey

The C240 and c320's have wires that go from the coil packs to the dual plugs

KalC240

The 240 has 12 wires, and at 100K you should replace them. Or you can check each wire for its resistance to see if it's Ok. I got a set of 12 wirers for $60 on Amazon.

Glyn M Ruck

Use the correct OE Bosch or NGK plug. You are in the area that wires can give trouble.

ncmudbug

Glyn, I didn't notice where vhouc lives. What sort of areas require plug wire change? What happens to them? What sort of frequency? Should the coils be changed with the wires?
Thanks!

KalC240

I think Glyn is referring to your mileage. Wires are not much affected by geographicl area

Norwichdelta06

put it this way you are probably never going to do the plugs or wires again. Spend the extra money... And honestly in my experience I have never scene a difference among different spark plugs... You can feel the difference when you change your OLD ones and put in NEW ones but if you put OEM Bosch or NGK you will probably not notice the difference between them

ncmudbug

Yikes! pretty obvious when I read it again!

Glyn M Ruck

The plug wires live in a hostile environment - vibration & heat. Insulation etc breaks down over time. The odd misfires start coming in over 100K miles & you can get stuck on the side of the road.

I would not replace coils until failure. They are expensive & pretty erratic on the sort of life they give.

ncmudbug

Thanks, Glyn! With silicone wires (does MB use silicone?), I never worried about them before.

Glyn M Ruck

It depends when in MB life you are talking about.

Most M112 engine plug leads have carbon impregnated fibre cores (Kevlar or CF) with silicone insulation.

vhouc

thank you guys! I replaced all ignition wires too and the spark plugs, i noticed a huge difference in fuel efficiency. Before, in a week I have to re-fill my tank, i've been driving it for a week now and I have a little less than half tank. same distances and same routine.

KalC240

good job. how many mile have you done on the half tank (8 - 9 gal?)..

vhouc

176 miles

vhouc

anyone....i know about the STFF. No matter how I tried I cannot find where to find mod kits for my car. Looking to change the door sill and front bumper any links?

FraKctured

Replace the wires. It's worth the extra money.

vhouc

Fraktured, yes I took ur advise and I replaced it with bosch ignition wires as well. The store does nt have ngk wires, its less expensive anyway spent $243 for the wires.

Glyn M Ruck

Good news.

jtwillia2

Would this situation and advice be the same for a 2005 C230K SS? I'm about to replace my spark plugs at 78k miles and the only wires I can find are these:

http://www.partsgeek.com/catalog/200..._wire_set.html

Thanks.

KalC240

first make sure you really have "wires" connecting the coils to the plugs, or is the coil connected directly over the plug, in which case there are now wires for you to buy. Open the hood and check.

KalC240

Partsgeek.com show that you can replace the coil boots, but i don't think you need to do that unless the is damaged...

Glyn M Ruck

The M271 engine is coil on plug. No wires to replace like M112 V6 models. M272 is also coil on plg.

ncmudbug

Is there any issue with the low tension wires to the coil? Do they need to be looked after?