How does this plug look?

[wheela]

Hi all,

I'm not experienced reading plugs, so I thought I'd post up some pics to gather peoples' thoughts on how it looks. Does this appear reasonably healthy?

Background on the plug - it's from cylinder #2 in my n55, running MHD stage 2+ 93oct tune. The plug has about 5k miles on it, no special gapping, just the standard plug the dealership put in when I had them change my plugs.

I pulled it, because I all of a sudden had bad misfires and limp mode from cylinder 2. When I opened it up, the #2 coil was fully loose. I pulled the plug for good measure, and it didn't take much force to break it loose. I think maybe it wasn't tightened properly to begin with, and started to loosen until some combustion gas could get through with enough pressure to pop the coil out of the hole. I wiped off as much soot as I could, wiped down the insulator and contact with alcohol, and put the plug back in, torqued it to 17 ft*lb, per FCP Euro. I also pulled all the original Delphi coils and swapped in brand new Eldors from FCP Euro.

There was some soot in the threads, and also black around the base of the insulator. Any thoughts on how this looks?

Thanks!!

 

[wheela]

I tried comparing it to this chart, but it's hard to say where to put it. I'm thinking anywhere from perfect to running hot/lean?

 

[ShocknAwe]

Looks like some arc damage from the poorly seated coil, I definitely recommend a gap tool and a tube of dielectric grease.

 

[wheela]

Looks like some arc damage from the poorly seated coil, I definitely recommend a gap tool and a tube of dielectric grease.

Thanks for responding! Do you see any issues continuing to use the plug? Since i've put it back I haven't had any misfire codes, and cylinder 2 doesn't seem to be correcting any worse than the others.

Do you have any thoughts how the ground strap and electrode look?

 

[Torgus]

Thanks for responding! Do you see any issues continuing to use the plug? Since i've put it back I haven't had any misfire codes, and cylinder 2 doesn't seem to be correcting any worse than the others.

Do you have any thoughts how the ground strap and electrode look?

My only thought is if you are going to take plugs out your might as well replace them. I know plugs are insanely easy to do on this motor but if you buy them from FCP lifetime plugs and all of that: https://www.fcpeuro.com/products/bmw-silzkbr8d8s-spark-plug-ngk-97506

 

[Alturiak]

My only thought is if you are going to take plugs out your might as well replace them. I know plugs are insanely easy to do on this motor but if you buy them from FCP lifetime plugs and all of that: https://www.fcpeuro.com/products/bmw-silzkbr8d8s-spark-plug-ngk-97506

+1 on getting your plugs from FCP Euro. I've been swapping mine out every oil change using their warranty!

 

[ShocknAwe]

+1 on getting your plugs from FCP Euro. I've been swapping mine out every oil change using their warranty!

Agree to replace but every oil change maybe excessive.

 

[wheela]

My only thought is if you are going to take plugs out your might as well replace them. I know plugs are insanely easy to do on this motor but if you buy them from FCP lifetime plugs and all of that: https://www.fcpeuro.com/products/bmw-silzkbr8d8s-spark-plug-ngk-97506

Thanks for passing along that link! I was already considering trying going 1 step colder, I'll have to give these a shot Is there a decent gapping tool you'd recommend? This will be my first time gapping plugs, haha!

Yeah, pulling the plug was off the cuff - I only planned on swapping coils since the plugs had only 5k miles. But when I saw the #2 coil popped loose, I thought I better take a look at the plug while I had it all tore apart.

I wanted to clean out the plugwell a bit while the plug was out, but I was worried about accidently knocking debris into the combustion chamber. So I focused on cleaning up the plug and left the well alone. All the other plug wells looked spotless, but there is a little black at the bottom of the #2 well. Doesn't look too bad to me, but it's the first set of plug wells I've looked at.

 

[Torgus]

Thanks for passing along that link! I was already considering trying going 1 step colder, I'll have to give these a shot Is there a decent gapping tool you'd recommend? This will be my first time gapping plugs, haha!

Yeah, pulling the plug was off the cuff - I only planned on swapping coils since the plugs had only 5k miles. But when I saw the #2 coil popped loose, I thought I better take a look at the plug while I had it all tore apart.

I wanted to clean out the plugwell a bit while the plug was out, but I was worried about accidently knocking debris into the combustion chamber. So I focused on cleaning up the plug and left the well alone. All the other plug wells looked spotless, but there is a little black at the bottom of the #2 well. Doesn't look too bad to me, but it's the first set of plug wells I've looked at.

BMS Billet Spark Plug Gapper Tool

This precision tool is critical to properly and accurately gapping spark plugs. With this tool you will be able to gap plugs faster and maintain accuracy. Available in 14mm and 12mm plug thread sizes. Made in USA.

burgertuning.com

PR makes the same thing. This is probably the easiest way to gap plugs correctly. It also comes with the 4 feeler gauges you would probably ever use on the N54. You can always buy a full set for small money.

 

[wheela]

BMS Billet Spark Plug Gapper Tool

This precision tool is critical to properly and accurately gapping spark plugs. With this tool you will be able to gap plugs faster and maintain accuracy. Available in 14mm and 12mm plug thread sizes. Made in USA.

burgertuning.com

PR makes the same thing. This is probably the easiest way to gap plugs correctly. It also comes with the 4 feeler gauges you would probably ever use on the N54. You can always buy a full set for small money.

Thanks for passing this along!