Check the level. Check the fuel pressure. Check the O2 sensor. It sounds like too much fuel is being injected and excess is seeping by the piston rings into the oil. You may also be experiencing an oil pump getting ready to die. What is the RPM at idle?
February, 12, 2012 AT 8:54 PM
An injector or fuel pressure regulator is leaking and raw fuel has gotten into the oil and diluted it. Typically that reduces the oil's lubricating properties and the engine bearings are damaged. Excessive bearing wear lets the pressurized oil run out too easily resulting in low pressure. That's worse at low engine speeds when the oil pump isn't running very fast.
The first thing is to find how the gas is getting into the oil and fix that. Next is to immediately change the oil to get that gas out. Any driving like that is going to increase the accelerated wear. Next is to measure the oil pressure with a mechanical pressure gauge to see if it is acceptable. It IS possible the bearings don't have much damage yet and the low pressure is just due to the oil being diluted and thinned out by the gas.
February, 12, 2012 AT 8:59 PM
I would also check compression.
March, 31, 2012 AT 4:36 PM
Check and see if your car has a recall on the fuel pressure regulator. That could be your problem and they will fix for free.