[s-cars] Identifying Bad Coil

[James Murray (QB/EMC)]

Never personally tried the procedure, but it sounds logical as a test. A
"Megger" is usually a good test for a coil, but if you don't have one the
procudure below looks like it's worth a try...

Best of luck.

/Jamu.

-----Original Message-----
From: Brian Powell [mailto:powellb at gmail.com]
Sent: Tuesday, November 16, 2004 5:01 PM
To: James Murray (QB/EMC)
Cc: s-car-list at audifans.com
Subject: Re: [s-cars] Identifying Bad Coil


> I use this test all the time it never fails. The reason the tester is so 
> effective is because you're dynamically testing the coil. 
> As you know when the spark plug is in the cylinder ,the spark has to under

> extreme pressure try and ionize the gap.This puts extreme loads on the 
> igniton coil secondary circuit when your are under load/boost. This tester

> will simulate this condition every time. 
> We have a $30,000 dollar ignition scope at work. I'll still trust this
test 
> over that piece of equipment on any give day." 

James, thanks for the procedure. I will give that a try. I have an
adjustable spark gap tester, and I have tested the coils to the 40,000
volt level of the tester without any problem or difference between
them. The coils all work perfectly until I get to 20+ psi of boost and
then one seems to miss.I'll try varying the gap length to see if one
loses its spark quality before the others.

Cheers,
Brian