I recently was asked this question:
“I have a 2009 Mini-Cooper and it goes through oil like my kids go through milk. I have to put in at least a quart a week, sometimes more. My mechanic says it’s not leaking oil anywhere. Why would it be burning so much oil?”
If your car has less than 100,000 miles on it, and you are adding oil to your car’s engine in between oil changes, you probably are experiencing excessive oil consumption. This is a common problem with several European vehicles including Audi, BMW, & Mini-Cooper, and also occurs frequently in Subaru’s.
It’s normal for your car’s engine to consume oil over time. One quart of oil per 1000 miles considered acceptable by most manufacturers. However, any more than that or any faster than that is considered excessive oil consumption and indicates a problem. If your car is experiencing excessive oil consumption when it’s newer, the problem will only increase as your car ages.
According to a study by Consumer Reports, high oil consumption is actually very rare. Only two percent of vehicles manufactured after 2010 experience that issue.
High oil consumption can be caused by several factors:
- If you purchased your vehicle new and there are less than 6,000 miles on the engine, it’s normal for it to consume more oil as the engine “breaks in”. However, once it breaks in, the oil consumption should decrease.
Other causes of high oil consumption include:
- Towing heavy loads or driving at high speeds
- Driving in excessive heat, city driving, or both
- Overfilling the engine with oil
- Using the incorrect viscosity of oil
- Using diluted, contaminated or the wrong type of oil.
- Leaks: Seals, piston rings, valve seals, gaskets
- Using the incorrect fuel
- Dirty, clogged valves
What to do when your vehicle is burning too much oil.
- You want to check for obvious leaks in your system.
- Make sure you are using the correct motor oil as indicated in your owner’s manual.
- For vehicles that require synthetic oil, try switching to Mobile 1’s 0W-40 Advanced Full Synthetic Motor Oil, European Car Formula.
- Get your oil changed every 5,000 miles. The manufacturer says that you can wait 15,000 miles between oil changes. However, there’s a problem with that. The oil capacity on the Mini-Cooper is only 4.2 quarts. If it burns one quart of oil every 750 miles, you can see that you’re going to run out of oil before your next oil change.
- Make sure you check your oil level every week. You don’t want to take the chance that it will burn up all the oil and ruin your engine.
- Check your intake valves for carbon build up which will clog up the system and cause you to burn oil. If you have carbon build up, your local mechanic should be able to perform a service similar to walnut blasting to clean out the system.
- Ask your mechanic to use BG Fuel Injection System Cleaner or something similar to protect and keep the engine rings clean.