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Old 09-27-2011, 03:22 AM
Jase007 Jase007 is offline
Wrenchin' fool ...
Location: nova
 
Join Date: Jun 2004
Posts: 777
Mein Auto: e39 528it
Unless you have an oscilloscope handy ... the resistance check won't net you a bad coil.

The low voltage used by typical multimeters when measuring resistance is not enough to properly test the secondary windings. See if your indy has a "megger" or, read up on using an O-scope (borrow) to test.

I ran the Bentley tests when I got a stumble / misfire on one coil pack. Primary resistance was "in spec" and gave me no info. OBDII code "suggested" which cylinder and I swapped with another. Misfire followed the bad COP (coil on plug) and so I replaced with aftermarket Bremi (made in Tunisia). I investigated the OKD and Bavauto High Perf COPs and decided no. A month later, another misfire .. two COPs this time, different cylinders than previous. Again, primary resistance test showed nothing ... swapped with "known" good ones and misfire followed bad COPs.

At this point ... with three going bad in the space of 2 months, decided to replace all with new (that I hadn't already replaced) and new boots. Got new Bremi's from Tischer / Mileone BMW (getbmwparts.com) and all were BMW boxed Bremis ... made in Tunisia.

This was around 10 years old and 170XXX miles.

No problems since.

Good luck.
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2000 528iT Sport 5M (mfg. 5/1999) ~ 1990 325iX 5M
BMW CCA member #130075
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