Spark Plug Cracked (12 21 06)

Publication date: 2006-10-05
Reference number: 12 21 06
Supersedes refnos: 12 201 03

SPARK PLUG CRACKED

TECHNICAL SERVICE BULLETIN

Reference Number(s): SI B 12 21 06, Date of Issue: October 5, 2006

BMW:	E46, 323i with M52TU up to 03/00
GROUP:	Engine Electrical Systems

Superceded Bulletin(s): S.M. B12 201 03, Date of Issue: July 2005

NOTE: This Service Information bulletin supersedes S.M. B12 201 03 dated July 2005.

SUBJECT

Spark Plug Cracked

SITUATION

Check engine light is illuminated and misfire faults with cylinder injection cutout stored in DME module. Vertical crack found in spark plug porcelain insulation.

CAUSE

Insulation failure in spark plug extension socket.

PROCEDURE

When the above-mentioned fault is encountered, on a customer complaint basis, replace cracked spark plug (NGK plug PN 12 12 9 071 003 or Bosch plug PN 12 12 0 141 871) together with a defective spark plug extension socket (PN 12 13 9 067 831).

IMPORTANT: Replacing cracked spark plug only will not prevent fault from reoccurring.

WARRANTY INFORMATION

For information only.