Spark Plug Analysis

[Yeedogga]

Hi guys,

It's not a Skyline, but I thought I would ask the brains trust on here for some advice on this plug I pulled from my 1993 BMW 318i (E36)

Cylinder 4 (closest to firewall)

Brown, solid deposits on plug.. ewww

The car was running OK and there was no appreciable difference after changing the plugs!

Any ideas?!?

[vidospace]

Rust on the plugs is normally head gasket issue isnt it?

[ClutchBurndout-:(]

theres your problem right there

if there was that much water getting on the plug then the engine wouldnt run right, it would miss and carry on...

[rgr34]

im surprised that plug had spark.... and the car ran smooth....german engineering right there haha

[Yeedogga]

Yeah.. and returned 9 litres/ 100km whilst at it!

[t_revz]

i was going flat out up a hill when my fuel pump let go. detonation went sky high and i ended up with 5 broken pistons, 1 melted piston and 4 spark plugs that looked melted like that

[Kinks]

yikes. the car was only running right because it was nowhere near its potential to start with

man it looks like it caught VD in some of those pics. I'd be guessing oil/water contamination or something foreign getting through (past the air filter?)

what do the other plugs look like?

[Humbla]

Take it to a mechanic asap,that looks really scary.

[Yeedogga]

AFAIK, it had the head pulled by Trivett BMW when it was alot younger and it has never been the same since.

The other plugs look normal, one was a little bit fouled.

Im thinking possible cracked head on a water gallery (no coolant in oil) but i am hesitant to do anything about it as it is my daily and i dont want to make it worse!!

Could fuel contamination/ e10 fuel cause this?

[defari]

http://www.denso.com.au/Products/Aftermark...Used-Spark-Plug

PRE-IGNITION A melted or burned centre and/or ground electrode, blistered insulator and aluminium or other metallic deposits on the insulator.

Symptoms: Loss of power causing engine damage, pre-ignition occurs when combustion begins before the timed spark occurs.

Causes: Plug insufficiently tightened. Engine insufficiently cooled. Ignition timing too advanced. Plug heat range too hot.