tell me my MIS-fortune, read my plugs

[}{arlequin]

pulled these from my car recently

I'm not much of an expert so they don't tell me much. Any opinions? Thank you.

[kstylianos]

Dave,

Flip them around so we can see the electrode end. Can't really read too much into them by looking at their sides. From what I can see, the engine could be running a little rich (dark sooty electrode on #5), with a possibility of a little oil. Rich is ok, especially if its tracked regularly in hot weather. Overly rich is bad as the gas can wash the oil off the cylinder walls, pass the rings and dilute the oil.....doesn’t look like this is the case.

Flip them so we can get a better look.

BTW: Bosch Copper plugs are said to be better suited for our engines.

Here is a good pic for reference:



Spark plug reading bible:

http://www.dansmc.com/Spark_Plugs/Spark_Plugs_catalog.html

[}{arlequin]

thanks Charlie, how about these? This was the first set that I put in right after I got the car so I wasn't clued in to the copper issue. I'm already looking around for those. I drive it pretty hard.

[kstylianos]

Honestly, they look just about perfect!!

I wouldnt touch a thing.

[aigel]

They look good to me. Some white is normal, especially with todays funky fuels. They all look the same which is good too. Put regular copper plugs and keep running...

George

[}{arlequin]

Originally posted by kstylianos
Honestly, they look just about perfect!!

I wouldnt touch a thing.

Whew, glad to hear that. Thanks.

[Purrybonker]

This plug reading stuff is nothin' but a buncha old wives tails...

(well within reason, anyway)

My plugs were blessed by three "ace Porsche wrenches" as being indicative of beautiful running condition whereas the engine was actually in need of valve guides. Not that any mortal could have caught this by looking at plugs - just a point of interest...

Since I have acquired and played around with an LM-1, I have experienced the following:

* With the engine running way rich at WOT based on LM-1 observations the plugs have been diagosed as indicative of running far too lean.

* With the engine running lean based on LM-1 data, the plugs have been diagnosed as indicative of good AFR.

In other words - reading plugs to guess at AFRs is pretty much a waste of time these days and could well be dangerous to the health of your engine and bank account. Spring for an LM-1 and erase all doubts.

[Early_S_Man]

Those appear to be W3DP0 plugs ... which are the wrong plug for your engine, as they are way too cold, even for a 911S when driven on the street in everyday traffic!!!

The correct plug from the Bosch USA web site is W5CC or W5DP0. The Bosch copper core plug is the way to go ... or NGK BP6ES or BP7ES.

With unleaded gas ... plug reading is pretty much useless. Those plugs are too cold, as indicated by the carbon buildup on the body, and 'smoky' appearance of the center insulator! How many miles on the first set you posted??? My best SWAG would be less than 5000 miles ... a waste of money, at best!

[}{arlequin]

Thanks Warren. You are correct, those have approx 6k miles on them. As I already stated, this was my first set I installed after I got the car, but before I jumped into the whole plug-applicability knowledge. I am currently stocking up on copper plugs in the correct heat range.