Temp Indicator and Oil press wire

1998 1.8T passat, the temp indicator on instrument panel flashes till warmup and it goes a way. This happens only when engine is cold the first start in the morning. I changed the sensor behind the engine but did not help!

I changed the oil filter and found two wires, one goes to the pressure switch on top of the filter and the other just hangging loose. Both ends are coming from the same wire harness. Is it poosible that VW leave such a wire loose!! I culd not find where it connect to. It is a female end wire connector!

Thanks

Is the coolant reservoir at the correct level cold?

Dummy... Its the coolant resivour level sensor plug. It plugs directly into the bottom of the resivour and you HAVE to unplug in order to move the resivour far enough foward to reach the oil filter. Plug it back in and cycle the ignition switch a couple times and see if that helps.

Dummy... Its the coolant resivour level sensor plug. It plugs directly into the bottom of the resivour and you HAVE to unplug in order to move the resivour far enough foward to reach the oil filter. Plug it back in and cycle the ignition switch a couple times and see if that helps.


This is not true, The coolant resivour has it's own connector and it is connected. This loose connector is a split from the wire harness that one side is going to a switch on top of the oil filter and the loose wire is not long to reach the coolant resivour. Please respond.

Vw has had problems with coolant resivours on 1.8t's where the coolant lite will flash uuntill the car has warmed up. You have to pressure test it and check the level sensor.

To test the sensor- hook up a ohm. meter to both sides of the terminals on the resivour w/ the connector off. slowly fill the resivour and it should go from 0fl to a high resistance when full. IF it doesnt, than the sensor is bad and you need to replace the resivour.

Might also have problems with water pump.