BimmerFest BMW Forum banner

Spark Plug Diagnosis

3K views 11 replies 5 participants last post by  Fast Bob 
#1 ·
Hey everyone. I've already compared the plugs to a diagnostic chart but I'm hoping you all might give me some good unbiased input. These were replaced today on my '05 X3 with 97K miles on the odometer. I've only had the vehicle a few weeks so I'm not sure if the plugs were original or not; perhaps they were changed at the dealer once before. They seem to show good signs to me, but what do you all think? Anything I might need to know?
 

Attachments

See less See more
4
#3 ·
Looks pretty average for plugs that have been in there for awhile....
 
#12 ·
I remember when the quad-electrode plugs were first introduced around 25 years ago, and recall that the reason given for their design was to be more efficient in engines with higher-than-usual combustion chamber pressures, i.e., forced-induction and high-compression N/A engines. There were lots of turbo motors around back then.... it`s always been controversial as to whether the plugs actually help or not....
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top