Water in the engine oil fill question and others

My dad has a 1998 Cadillac Catera. He has three queations about problems he is having.

1. Everytime we open the engine oil fill, there is a a layer of milk-like substance, kind of like when oil and water mix, but there is no water in the oil. What could this be?
Someone suggested pcv, but I know we do not have a pcv. Any ideas?

2. When we turn on the heater, only the drivers side warms up but the passengers side doesnt even though both climate controls are set to hot.

3. Temp gauge does not work properly. We have changed the Coolant temp sensor and the gauge sensor but still doesnt work. Ideas?


Thanks in advanced,

Mike

1. Everytime we open the engine oil fill, there is a a layer of milk-like substance, kind of like when oil and water mix, but there is no water in the oil. What could this be?
Someone suggested pcv, but I know we do not have a pcv. Any ideas?


This is not really a problem. It is normal for engines that are used mostly for short trips.
Engine oil gets contaminated by blow-by gases as the engine runs, and by condensation that is produced when engines cool down after running.
Most engines will boil-off these contaminents from the oil as the car is driven on longer trips. However, if you only ever drive the car for short tips, (less than 30 minutes or so) the oil never gets warm enough to purge the contaminents so they accumulate in cool parts of the engine, like the oil fill cap.

Check the PCV system and see if it is clogged. Otherwise, just be sure to change the oil regularly, even if the mileage driven remains low.

what about the other (very valid) questions ??

Ok, other questions, let's see maybe the t'stat is bad showing low temps you did not explain what the temp gage does, no? The seperate hvac controls are operated by the bcm and use mode door actuators, a full scan wtih a bi-directional scanner can command those actuators for a proper diagnosis, but the temp issue may be related. BTW, this is a almost 2 year old dead thread so why the concern?

well, no REAL concern,,,for question #2-my hvac does the same thing, and i was looking for an answer that might help me out. as long as some of the cars are still on the road, and people are still working on them, is a thread ever REALLY dead ??

It is an issue of inactivity and low participation when it is this old, not an issue of whether they are still on the road, that is not clear thinking. A new post would be in order to attract more participation.