Hiccups - PeachParts Mercedes-Benz Forum

E150GT · #1 02-28-2007, 09:54 AM

I changed my spark plugs yesterday with dealer plugs on my420sel. It now seems to have "hiccups" at idle. It idled a litlle rough sometims but now it has a prounounced miss i guess sometimes. Also i found a little oil on three of the spark plug threads. should this be a concern?

david s poole · #2 02-28-2007, 12:50 PM

make sure that your plug wires are good and make sure that you "clicked" each of the boots to the plugs.[p.s. if you have bosch plug wires go directly to your parts place---do not pass go--and do not collect 200 doll and buy a set with BERU plug ends on them].

E150GT · #3 02-28-2007, 03:44 PM

Not what I wanted to hear. I just spent 231 dollars on dealer bosch wires and beru plugs.

Surf-n-Turf · #4 02-28-2007, 04:04 PM

When you installed the new plugs, did you leave the little metal caps screwed on? In my 420SEL I had to take them off to seat right.

E150GT · #5 02-28-2007, 04:34 PM

Yes. The wires would not fit on them without removing those little metal thingies. Thread protectors?

david s poole · #6 02-28-2007, 05:26 PM

the dealer just keeps those wires to pacify the diy crowd [and of course for mucho profit] i can and do buy complete sets of beru wires thru worldpac.as an aside i put a bosch rep on the hot seat at a trade fair here in dallas about a year ago and he promised to research the question of the ****ty wires and get back to me.i'm still waiting.

E150GT · #7 03-01-2007, 08:38 AM

So I just wasted 200 dollars?

graftdesign · #8 03-01-2007, 03:31 PM

Yeah, the Bosch wires of today are crap. My originals actually were better after I put on new set believe it or not!