Q: I own three Toyotas and I change oil and filters every 4,000 miles. My 1998 Land Cruiser with 217,000 miles and my 2004 Sienna with 168,000 miles use no more than ⅓ of a quart of oil between oil changes. But my 2008 RAV4 with the 2.4-liter four-cylinder engine consumes about 1 ¼ quarts during each 4,000-mile oil change interval. This consumption hasn't changed since new. I realize Toyota considers this to be "normal," but I'm concerned whether this is an indication I shouldn't expect to reach my "normal" 200,000-mile-plus life from this vehicle.
A: I don't think so. This rate of oil use is completely normal and should not affect engine durability or life expectancy. The only thing I can say is this: It is what it is. We had an '88 Taurus purchased used with 60,000 miles on it that used a quart of oil every 1,500 miles for its entire life. I found the car four years after we traded it in and the owner reported it was still running strong at 180,000 miles.
To put oil consumption in perspective, if your engine burned one drop of oil per cylinder/combustion cycle, it would consume a quart of oil in less than 10 miles.
Q: I have a 1978 Datsun 280Z and a 1985 Chevy pickup truck. Both have low mileage and are in good shape. I keep them in an unheated garage from November through April. Is it a good idea to start them once a month during these winter months?
A: Consider this "long-term parking," not storage. I don't think it's necessary, nor necessarily a good idea to periodically start/warm up a vehicle in this scenario. Each cold start is without doubt the most stressful operational moment for any engine — thicker oil, longer time delay in pressurized lubrication reaching critical components like cam lobes, main and rod bearings, thermal shock on pistons, valves and combustion chambers — just to name a few. Granted, engines are designed to deal with this stress, but obviously the more often this occurs the more wear and tear.
In addition, as the engine initially warms up, moisture inside the crankcase condenses into liquid form, contaminating the oil. If the engine is not operated at full temperature under reasonable driving loads long enough to evaporate and remove this moisture via the PCV system, sludge and "glop" will begin to form.
My suggestion is to take a few simple steps to prepare the vehicle for "long-term parking," then leave it alone until you're ready to drive it in the spring.
It should take less than 30 minutes per vehicle. Fill the tank with non-oxy fuel, add SeaFoam, disconnect the battery, charge it monthly or leave it on a battery tender/maintainer, fresh oil/filter, tires inflated to 10 psi over their recommended pressures, dryer sheets placed throughout cabin, trunk and engine compartment, windows down a fraction of an inch to allow airflow but no critters, and a car cover if you have one.
My 44-year-old Corvette with its original engine has survived "long-term parking" every winter for the past 36 years.
Q: The check engine light comes on after I drive my 2003 Jaguar XJ8 only 1 ½ miles. The car runs well. These are the codes that were read: P1642, P1000 and P1571. What can you tell me about this problem?
A: The P1000 code indicates that the OBD (on-board diagnostic) system has failed its self-check. The P1642 code indicates a CAN (controller area network) short-circuit fault. The P1571 code refers to a problem with the brake on/off switch or an open or shorted circuit to the ECM.
My ALLDATA database pulled up several service bulletins from Jaguar pointing to problems with harness connectors/pins under the dash and under-the-hood causing similar multiple fault codes. Start with the ABS/DCS connector in the engine compartment. Good luck!