So I finished up the X5 yesterday.

I changed the oil with Penzoil Euro 5w40, replaced the air filter, changed out all the plugs with NGK Iridium, dumped a bottle of Gumout Rengane, and cleaned the crankcase ventilation valves. The car is noticeably smoother at idle with the new plugs. I haven't noticed the engine running any quieter running the 5w40. The crankcase valves were not NEARLY as gunked up as the pictures I've seen online. I DID however notice tears in each of the rubber boots...which will be replaced shortly.

I'm still not convinced that any of these caused the car to randomly shut off. But after seeing the plugs, I CAN see how they'd misfire.

These are pictures of the plugs. I'm not sure what the cylinder numbers are, but starting with the the front of the car working back on the drivers side, then back to the front working back on the passengers side...










Thoughts?

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'00 ///M5 * '04 4.4 X5 * '95 540i/6 * '80 528i