[Diy_efi] OT - platinum plugs burning up wires

[David Allen]

  Didn't hurt my 1991 TBI 305 with stock ign. components.  Hasn't hurt my
mother's 1989 LeSabre with Series I 3800 and DIS ignition. On all these cars
the ignition leads last fine.  Had one coil failure that I couldn't explain
on the 305 but I was using a coil of unknown origin.
  Modern graphite core wires can be fickle.  The core may be brittle; or the
wires may be stressed or pulled during the service.  A crack opens in the
core and as the ignition fires across this crack it burns away more and more
of the core. Finally the wire is open-circuit.
  However my turbo engine does not run as well with Bosch Platinums as it
does with standard plugs.
  Maybe I am just lucky with not ruining ignition leads?
David


----- Original Message ----- 
From: Bret Levandowski
To: diy_efi at diy-efi.org
Sent: Saturday, September 10, 2005 5:26 PM
Subject: Re: [Diy_efi] OT - platinum plugs burning up wires


Platinum plugs have a higher core resistance and require more current and
more precise control to fire. This is not true of all platinum plugs but
most. If the resistance in the plug or across the gap is too much, the
current can't 'escape' through it's normal path and it has to go somewhere.
Always the point of least resistance, whether it is the cap/rotor or plug
wires it is going to flow somewhere. Either way, it is going to burn
something up; possibly even your coil.
I have experimented with different plugs and different systems and have seen
all types of failures. From what we saw, AC Delco platinum plugs will burn
up coils and wires quite nicely on older motors. SureFire triple platinums
work well in just about any type of performance motor (high comp/high energy
ignition), but not so well in older or lower compression motors. It wasn't a
'scientific experiment', just what we saw happen by changing plugs. So after
much rambling..... Yes, what the tech said is true. You can burn up ignition
components using platinum plugs in non-platinum applications. I have done it
myself and had to have someone else tell me why. Unfortunately, you don't
know 'til you try.

Rick McLeod <dunvegan at sbcglobal.net> wrote:
Sorry for being off topic, but I know there is a lot
of knowledge in this area on this list, and this might
be of interest to discuss (remember the recent plug
discussion?)

Recently I had an issue w/ a Hyundai where the plugs
were replaced w/ platinum at a tune up. A few k-miles
down the road, the car began running poorly, and was
taken to the dealer where it was diagnosed as having
'burned up ignition wires'. The service advisor stated
that you MUST NOT use platinum plugs in these cars
since it will cause this to happen.

My question is: What is different about them that
would cause this, it sounds like 'bunk' to me, but am
looking to the vast world of knowledge on this list to
get some insight.

Thanks

_______________________________________________
Diy_efi mailing list
Diy_efi at diy-efi.org
http://lists.diy-efi.org/mailman/listinfo/diy_efi



Click here to donate to the Hurricane Katrina relief effort.



_______________________________________________
Diy_efi mailing list
Diy_efi at diy-efi.org
http://lists.diy-efi.org/mailman/listinfo/diy_efi