Any help would be great? I have a 2000 GTI turbo and the low oil pressure warning keeps coming on I have replaced the switch and pickup pipe in the sump. Any ideas? How can i test oil pressure?

get a oil pressure gauge. Maybe you have a leak somewhere?

I believe there is 2 oil pressure switches, one on the oil cooler and another on the head. I would say replace the oil pump because its a 00, but a bad cam adjuster would cause oil pressure light also.

Don't forget about oil sludging (even though VW says it only happens on the Passats) & the oil pump.