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Oil & air filter discoloration

My 1994 Plymouth voyager with 128000 miles shows a milky oil substance in the air cleaner elements. The oil filler cap does show a very small amount of milky oil but the dipstick is clear of any milky substance. The antifreeze is ok, it has the normal color of antifreeze. It has been unusually cold in Virginia the past 3 weeks. Is this evidence of head gasket problems or normal cold weather problems?

It could be due to the crankcase ventilation not working properly (PCV valve) or even driving habits if most of your driving is the short hop variety.

The PCV should be serviced on a regular basis. Remove it and shake it. If it rattles like a rock in a can it’s good. If it doesn’t rattle or is erratic then it’s dirt cheap to replace it.

If your driving is mostly short hop then the engine oil should be changed more regularly.

I changed plugs, wires, distributor cap, rotor, pcv valve and did an oil change about 10 days 400 miles ago, I also changed belts too. I usually change the oil every 2500-3000 miles which is about twice a year. I did not touch the radiator or hoses yet. I drive 10 miles to work one way each day, 20 miles around trip. I just use the Voyager for work and do not take it out of town or on the Interstate because I am not sure the Old Girl will last much longer.
Thanks for the advice and information

I had the same problem with a 98 Windstar (wife’s) and a 95 Dakota. The ~8-10 mile commute to work was not enough to warm up either vehicle and burn off the accumulated moisture. I replaced the PCV valve on both vehicles and tried to do in a longer drive each week to burn off the moisture.

Just to be safe keep a close watch on the coolant level. I used a Sharpie to mark the coolant level in the overflow tank.

Ed B.

I agree with Ed B. If the vehicle is not losing coolant and based on your driving this is likely the result of driving habits.
Time is also a factor and since 2500 miles per 6 months is pretty severe you could try 3 month oil change intervals but it would help a lot to take the vehicle out on the road now and then for a 50 mile drive.

Moisture (not necessarily coolant) and oil combined will create a mucky sludge and that sounds like what is going on here.

There is more to a PCV system than just the valve. The vacuum port on the intake manifold can get plugged up too, rendering the valve non-functional…