I got this tip from Brad Mayeur. He said to unplug this 2 wire plug and the engine will run better. My engine is a 2.0L D-jet. When plugged in at cold start the engine runs well until engine warms up. Then it will die. If I keep it unplugged it runs fine. So what does this do and why does the engine runs better without it? Brad says that due to the age of the cars it doesn't work like it should. Just want to know why it is?

BuckClick to view attachment

AIS, runs richer when unplugged, IIRC.

So I see this is tied to your other thread on this. T1 sensor disconnected will run richer. But if the car is running leaner than it should why not find / solve the root cause? T1 is there for a reason.

Test to published specificaiton for resistance. It's either good or bad.

Wise words from @BeatNavy . No OEM just puts parts on a car that aren't needed. That costs money. Don't forget the cost of the wire, connectors, and the components inside the ECU to process that signal. When you multiply the price of that sensor x the 100,000 or so 914's that were built, you can bet VW wasn't just giving away that money because it wasn't needed.

Find root cause and fix.

I have never seen one go bad . Taking it out and cleaning it up might not hurt.