Ready to do the 120k service this week - Spark Plug question

This is my '99 daily driver. I plan to change the oil & filter, (every 5k), air filter, cabin filter and swap out the brake fluid. What plugs are the cool kids putting in their 986s these days? One electrode, two, four, ten?

Grant

gee-lenahan-at-gee-mail-dot-com

Thanks Grant, that's what I normally use, just ordered from Pelican. I replace mine every 30k too.

Are there any 100k mile spark plugs for the boxster?

You have to consider:

1. how often does the car run rich, for performance reasons?
2. How much performance degradation are you willing to allow?
3. How often is it used at high load?

.. and myriad other questions that may wear the plugs or demand less wear...

So my quick answer is "i suspect not"

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

the parts computer says belongs. For both cars I think all that have come out of the engines have been Beru plugs. The Boxster always has 4 electrodes, the 996 plugs only have 2.

Bosch and NGK. I coudl get the numbers, but they are pretty simple to cross. Beru costs a bit more and seems preferred based on feedback over the years.

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

Change the plugs early and often. As they wear, the gap increases which makes the coils work harder, so if you want the coils to last,z replace the plugs.

Do you simply get a longer arc, yet weaker spark?

What feedback loop causes the coil to work harder?

Or does the load change?

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

My understanding, and I'm not a rocket surgeon, is that the coil has to generate more power to bridge a longer gap, which lessens the life of the coil.

supplied with. The "quality" of the removal of this voltage also plays a role in the spark generated.

The spark occurs when the air gap resistance is overcome by the electrical energy generated. In some cases as little as a couple of thousand of volts is all that is required. In other cases the voltage required is of course much higher and then there is the delaying of the spark that can occur if more voltage is needed than is expected or in the worse case no spark occurs.

...it can work. Hence my question.

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

The Beru plugs arrived from Pelican Parts, along with the OEM Pollen, Air and Oil Filter and a Liter of ATE Brake fluid - regular, redish-brown I think. I used the Blue for my last flush & clutch bleed. Motive Power Bleeder has been a great investment!

Wal*Mart has Mobil 1 at $22.97 for the 5qt jugs. My local store has 0W-40 but I have been using the 10W-40 High Mileage for the last several changes. ~$160 for a 120k service and oil change... you won't see that bill from the dealer.

I replaced the serpentine belt, gear oil and fuel filter at 90k and replaced all 4 rotors and pads at 100k. Other than visually checking for leaks, any other routine items I may want to look at?

In the past, I've replaced the AOS, water pump and coolant tank & cap. After 120,000 miles and 14 years, she still runs like a top!

Quote
BoxsterBob - San Carlos
The Beru plugs arrived from Pelican Parts, along with the OEM Pollen, Air and Oil Filter and a Liter of ATE Brake fluid - regular, redish-brown I think. I used the Blue for my last flush & clutch bleed. Motive Power Bleeder has been a great investment!

Wal*Mart has Mobil 1 at $22.97 for the 5qt jugs. My local store has 0W-40 but I have been using the 10W-40 High Mileage for the last several changes. ~$160 for a 120k service and oil change... you won't see that bill from the dealer.

I replaced the serpentine belt, gear oil and fuel filter at 90k and replaced all 4 rotors and pads at 100k. Other than visually checking for leaks, any other routine items I may want to look at?

In the past, I've replaced the AOS, water pump and coolant tank & cap. After 120,000 miles and 14 years, she still runs like a top!

conditions.

Check power steering fluid level. A dropping level can be a high pressure valve is failing and routing too high a pressure fluid to the rack. The seals fail and the fluid leaks out to collect in the dust boots.

Check accessory drives for any play and pay particular attention to the water pump. Sure it is "new" but still... Check for any signs of coolant wetness.

Check the CV boots for cracks/splits. Check sway bar links and other suspension/steering links for looseness or signs of bushing wear or degradation.

Check the underbody panels for any missing fasteners or damage. Once I noted some of the nuts that hold that metal plate in place at the rear of the car had come loose. More recently I had to have the rocker panel cover on my 996 replaced the other day. Something kicked up from the road punched a big hole in it. Loose panels or panels with holes in them can make noise.

Since my cars are lifted by the lifting points (at the dealer) the tech can rotate the tires and look for anything in the tires. Last service he spotted a screw in the tread of the left rear tire which I had plugged/patched from the inside. At the same time he looks for any signs of fluid leak from the struts.

FWIW my high mileage Boxster (in a few days it will be at 270K miles) still runs Mobil 1 0w-40. No excessive noise. No leaks. No burning of the oil. No problems.

Mark, thanks for the suggestions, it is easy to omit items based on the assumption they are "new-ish". I think the next project (no due date) would be some suspension item replacements. 120k miles, mostly on the highway 101 Peninsula will take its toll on any suspension.

but come on over and try I-580 or I-680 or any number of roads hereabouts and you will appreciate just how bad roads are in this area, not just 101.

Check with a trusted tech but mine tell me my struts/suspension are just fine. The struts get checked for leak sign every service. -The only thing on my Boxster suspension related was the front sway bar links. The links were ok but one dust boot failed and I had both links replaced just to be safe. Oh, while not suspension related I had to have the CV boots replaced -- they developed cracks/splits finally -- and at the same time the tech cleaned/inspected the CV bearings and repacked them with fresh grease.

I'm sure I'll be doing the CV Joints some day. All four show no visual sign of failure. All 6 plugs all came out light caramel brown with no sign of fouling, also, no plastic or metal debris in the used oil. For some reason, the car just feels happier with a fresh fill of oil.