A friend of mine in Seattle has a 2001 (maybe 2002?) VW Golf that uses oil (~1 qt./1K miles) during the summer (when it’s hooter) but does not use any oil in the winter. When she asked her VW dealer mechanic what the cause was he shrugged his shoulders and said “Eh, it’s a VW.” That doesn’t sound right…any suggestions? The car uses the recommended oil weight (5W-30) and has been well-maintained with ~110K miles on it.
While I would expect a car that uses oil to use a little more during the summer than in winter, but not much. Are your usage different?
There is no oil usage during the winter months, only the summer months. In Seattle winter temps average around 40 F, in summer the average is in the 60s F with highs generally no more than 80-85 F.
If she does any fast driving in the summer that could explain it. Seattle has a very mild climate, so the summer and winter consumption should not vary for the same kind of driving.
I think that Doc is on the right track.
Also, since you tell us that she only goes to Hooters during the summer, the resulting heat factor from those visits might account for the difference.
Engine oil usage is directly tied in with how hard and long an engine is driven on a regular basis.
In the summer months, your friend is most likely going on longer trips, up into the mountainous areas, and stressing the engine harder. During the winter, they are most likely either not doing this, or are doing this not only less often, but at much reduced engine and vehicle speeds.
Engine oil, when it gets hot enough, can get turned into a mist inside the engine.
As the Crankshaft spins, and the pistons push up and down at ever increasing speeds, the oil mist gets sucked into the Crankcase Ventilation system, and ingested through the throttle body so that it is burned, instead of polluting the atmosphere.
Long periods of hot, high rpm driving is when this oil mist is produced, and ingested by the engine. Much less likely to occur during the cold of winter.