The reason an engine begins using excessive oil is that wear occurs in the internal engine parts which are supposed to keep the oil from getting into the combustion chambers. The oil then gets into the combustion chambers, is burned along with the fuel, and goes out the exhaust pipe. With this type of oil consumption; there will be no external leakage, and the motor will run well.
All engines consume oil to some extent. The rate of consumption usually increases as the engine ages. Engines in good mechanical condition commonly can go 3000 miles or more before they need a quart. It is generally considered that when an engine begins consumng a quart of oil in less than 1200 miles; it is using excessive amounts of oil and it should be repaired or replaced.
A short block is a remanufactured engine, minus the cylinder head. The service manager recommended that because it contains the main parts which would cause oil consumption if they were worn. That repair would cost you between $1500 to over $3000.
Before springing for such a major procedure; I would recommend trying some inexpensive approaches which often are surprisingly effective. New car dealerships are required by federal law to only use oil classified as "energy conserving" in all the vehicles they service. But this type of oil gives poorer lubrication than traditional oil; because it has been chemically diluted to reduce friction. The result is that it is consumed more rapidly than conventional oil; and may be consumed far more rapidly than desirable when used in older engines.
I would recommend having the oil changed, and using a quality 20W-50 oil instead of the oil the dealership has been using. You will probably have to have the oil changed at an independent shop or oil change place, because the dealership is not permitted to put 20W-50 oil in your car. The best brands of 20W-50 oil to minimize consumption are either Texaco Havoline, Kendall GT-1, Pennzoil, or Castrol GTX. It is preferable for a car to always use the same brand of oil whenever it is either added or changed. This is true because modern oil is about 40% additives and only 60% oil. Each manufacturer uses different additives in their oil. Although they all would like you to think it is perfectly safe to switch to their brand; the fact is that changing brands often results in sudden engine wear and increased oil consumption. However, in specific cases such as this one; it is better to change fron an unsuitable oil type to a better type, than to stay with an oil which is obviously not working well.
Another thing I would recommend is to have the valve stem oil seals in the cylinder head replaced. This is a relatively low cost procedure, and can make a major difference in oil consumption rates if it is needed. I would also have the PCV valve replaced and the PCV hoses checked for leaks or blockage.
There is one other thing you can do. which has been well worthwhile in my experience. Go to (www.kanolabs.com
) click on the "engine cleaners" link on the left of the home page, and click on the "risk free trial offer" below the Kreen Internal Engine Cleaner information. Order at least a quart of Kreen. This product is designed for use in both fuel and oil. The most effective way to use it is before an oil change: Add 1 pint to the engine oil (do not fill the engine oil above the full mark), and 1 pint to a full tank of fuel. Drive the vehicle for about 50 miles, and then have the oil and oil filter changed. It would also be beneficial to add a pint of Kreen to the new oil when it is refilled, again allowing room for the additional volume to be added.
If you decide to replace the short block; you could save a major amount of money by ordering a precision remanufactured engine from www.hiperformer.com
, and having them ship the motor to a local independent shop for installation. Compare the price of having this done with the quote you get from the dealership. Hiperformer engines is the most respected engine remanufacturer in the USA. They supply all the engines for the highly reputed NAPA nationwide chain of parts stores; and also sell direct to the public. Their engines come with a 7 year, 100,000 mile warranty. And you'll be getting a complete engine for probably less than the cost of a short block from the dealership. Call the contact phone number on their website for details.