brandobot

I've been searching for the past 45 minutes and can't seem to find out what the OEM Spark plugs are for the Porsche Boxster S (2013). I'm looking to order a set. Does anyone know which Spark Plugs work?

Pep!RRRR

brandobot

I found that link as well, but am curious to know what actual plug they're using. (copper, platinum, iridium, gap, etc..)

okie981

The OEM plug is made by Bosch, has 4 electrodes arranged 90 degrees apart around the central insulated electrode. Go to the Bosch website and get their part number for your car, then ask them about all the details you are interested in.

brandobot

Looks like the part number is FGR 5-NQE-04.. which make them a "copper plus" spark plug. I had always thought the lifespan of a copper plug was only 10-20k miles. Surprised Porsche says to change every 40k or 4 years.

okie981

I just changed the plugs in my BS at 26,000 miles but only because I was doing a header install and it was convenient to do them at the same time. They all looked clean with little electrode wear visible, nice color from normal combustion.

PorscheAddict

I did the same at the same miles (headers/plugs), albeit in an older 981S, 2014 (26k miles) and the plugs looked terrible. Corrosion on the threads and a hint of oil on some threads, with jet black electrodes. The car has seen a few track days and the plugs were at the 4 year spec to change.

brandobot

Thanks. Im going to change mind for peace of mind.

okie981

My plugs had 700 track miles on them out of the 26,000 total. As I posted elsewhere on RL, I did notice one cylinder (aft most on passenger side) that when peering up into the exhaust port, only one of the twin ports (again, aft most port) had a very light film of what I believe was oil over about 50% of the downward (gravity pulling) side of the interior surface. This same cylinder had a bit of visible oil on the spark plug threads when the plug was pulled. The threaded portion of the tip of the plug was slightly darker than the other 5 plugs in the same area. However, the insulated electrode, the insulation itself, and the 4 exterior electrodes were clean as a whistle except for normal healthy fuel mixture burn signature, like the other plugs. No buildup, no residue, nada. I posted my theory for what caused this oil residue in my other posts. Summary, is I have a theory it could be due to recirculated crankcase oil vapor draining down that aft most intake runner and through the valves when the cylinder parks with valves open at overlap (near TDC) which is exactly what that cylinder's position was when I took my OEM headers off after the car had been sitting for about 3 weeks and I peered up into all the exhaust ports. The inside of the OEM header tube on that port was again clean as a whistle, looked like all 5 others. I'm seriously considering doing RL member d00d's mod to bypass the air-oil-separator return to the intake manifold and put a catch can after the aftermarket air-oil-separator he's using in his mod. Check the GT4 forum for his "Pure White Journal" mods he's done to his white GT4. All the info about the mod is in there. Bottom line, DFI engines don't get a chance to wash the intake ports down with fresh gas spray and eventually carbon builds up in the ports and on the upstream side of the intake valves. Dozens of threads on the interweb for DFI cars of all makes. One thing that helps is to use oil that resists lighter fractions boiling off over time that prevents those fumes from getting to the intake manifold and condensing into oil again.