[W126 Coupe] HELP! resistor vs. non resistor plugs

[Richard Hogarth]

Oh yeah, 
back to your original question. 
Resistor plugs in the MB setup with stock wires and all will cause mucho
problemos. If you bought those pluge from a major reseller like autozone.
They will take them back without a hassle!. 
It's too much resistance, like taking a shower with an an eye-dropper for a
spigget. 
That's why I said gap them down to .028. (if you got less current, close
down the gap)
I'm sorry if our plug conversations skipped over resistor plugs. 
-Richard Hogarth


-----Original Message-----
From: mbcoupes-bounces at mbcoupes.com [mailto:mbcoupes-bounces at mbcoupes.com]
On Behalf Of Richard Hogarth
Sent: Wednesday, September 21, 2005 7:57 PM
To: 'Mercedes Coupes Mailing Lists'
Subject: RE: [W126 Coupe] HELP! resistor vs. non resistor plugs

That's curious. My oem plug wires only accept the non-threaded plug top.
I'll have to double check the manufacture of my wires. 
The resistor in the plug is giving you a significant drop in spark kernal
temp. 
Just for shits and giggles.  Pull the plugs and gap them to .028. 
What wires did you put in? Are they generic or MB?
Most plug instrutions say not to use anti-seize on the threads. Anti seize
is not a great conductor. But there is more than enough metal to metal
contact at the ft/lbs that it takes to seat a plug, tapered or gasgeted.
I've been using anti sieze for over 30 years on plugs. 
Don't completely goop up the plug, just a tiny smear vertically across the
threads from top to bottom. 


-----Original Message-----
From: mbcoupes-bounces at mbcoupes.com [mailto:mbcoupes-bounces at mbcoupes.com]
On Behalf Of Tom Oelsner
Sent: Wednesday, September 21, 2005 7:14 PM
To: mbcoupes at mbcoupes.com
Subject: [W126 Coupe] HELP! resistor vs. non resistor plugs

This afternoon I replaced my plugs to see if I could smooth out my idle that
occasionally ran a tiny bit rough.  RH...you cannot use Rapid Fire #4 plugs
as they have a one piece top that does not mate with the Bosch wires.  Also,
AC Delco says do not use any anti seize lube on threads...

So here is my problem.  The parts store did not have W9DC plugs in stock but
had WR9DC (resistor built in).  I queried him really hard about them and he
said they would be fine and would not impact performance.  So I gapped them
to .040 and put in new ignition wires (even though the old ones were only a
year old, I broke one pulling it.  So I replaced all.).  Well the car idles
really badly.  This is in spite of the fact that 3 of the older plugs were
really fouled.  So my question is obvious.  Are the resistor plugs causing
rough idle problems?

Tom Oelsner
90 560SEC


The MB Coupes Website!
W126 SEC Mailing List
Postings remain property of MB Coupes, L.L.C.


The MB Coupes Website!
W126 SEC Mailing List
Postings remain property of MB Coupes, L.L.C.