Spark plug Bosch or AC DELCO

Bosch components made in the EU (this is the important part) are in many cases the items that VW installed on the car in the plant, or better. Take the spark plugs for example, Bosch just prints the VW name on it and VW installs it in the engine.

I have just replaced the oil and all 6 spark plugs with Bosch Double iridium.

As for the spark plugs, both Bosch Iridium and NGK Laser Iridiums are fine, arguably even better than OEM (which are made by Denso, btw).

I have a stack of 25+ index cards filled with notes about the care and service of the car. The factory service manual has notes and highlighted areas all over it.

Replaced spark plugs with genuine VW Bosch units

Only use the factory AC-Delco 41-987 plugs.

i changed the original NGK spark plug with new Bosch super 4 spark plugs. a nice improvement but still far from old good performance.

Lesson learned: DO NOT EVER EVER EVER USE BOSCH PLATINUM (STANDARD TIP) SPARK PLUGS IN YOUR VR6 ENGINE.... THEY JUST DON'T WORK!

If you use anything but OEM plugs in a stock white block, well just don't do that. Also Bosch Platinum, great for having to pull your head and find out what the center of the plug did to your engine

For the OEM Bosch plugs, I would check them every 10k-15k miles at a minimum, based on what my stock plugs looked like @ 19k miles (sh!t).