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16v Ignition Woes



My car quit last week and, per the Bentley, I had a bad ignition control 
module.  I replaced it and the car started right up.  I've been doing other 
work so I didn't drive it much.  I started it up today and it ran for 
awhile, then it quit again.  It appears to be the ICM again.

When the first one failed, the test on terminals 1 and 15 of the coil 
indicated no voltage jump to 2 or more volts when I grounded pin 12 of the 
knock box connector.  On this one, I get a steady 7.5 volts on pins 1 and 
15 as soon as I turn on the ignition and nothing happens when I ground pin 
12 on the knock box connector.   Out of curiosity, I tested the 
coil.  Primary is 0.8 ohms and the secondary is 4K.  According to the book, 
the secondary should be between 6.5K and 8.5K.   I think the coil issue is 
secondary to the ICM problem though.  It should work OK at 4K, but it might 
be a little weak.  8v engines have 3.5K ohm secondary coils.

Also, on a side note, prior to the second failure, my fuel relay was going 
nuts.  Absolutely clicking like crazy.  I believe the signal that comes 
from the knock box (pin 12) actually starts with the ICM, doesn't it?

Soo...  a run of bad luck or is something killing my ICMs?  I noticed the 
ICMs are marked as rebuilt units.  There must be some kind of failure rate 
if they are rebuilding them.

Nothing was done to the car prior to the initial ICM failure BTW.  I do not 
believe I did anything to induce the failure.  I've just been driving the car.

That's enough.  I'm frustrated.

John
Long Beach, CA
87 16v