When i start my engine; the RPM's fluctuate below 1000 to 3000 rpms. Then when driving it doesn't accelerate properly kind of jerking back and forth between rpms. My synthetic oil had burnt up after only 3,000 miles and I had to add a full quart of Mobile 1 5w30 synthetic oil. Still having the same problems after making sure the oil level is correct. Any thoughts???

SOURCE: I have a mazda 626

Nope, it's not a problem. The numbers relate to the viscosity or slippery'ness (if thats a word) of the oil. The first number (5 or 10) is the viscosity of the oil when you first start the car. 5 is more slippery than 10. The second number (30) is the operating viscosity of the oil after your car has warmed up.
Simply put, in the winter your oil thickens when it cools down so you need smoother oil (5w30) when you start the car.
Winter = 5w30
Summer = 10w30
Hope this helps.

SOURCE: 5W30 or 10W30 for the 1.8L?

5w30

SOURCE: Oil light is on and oil is in the engine @ proper level

may be it's a problem with ur oil indicator

SOURCE: Loss of oil over time

Have you tried running conventional oil and see how much it burns? If it is truely burning that much oil, you have a problem with the rings not seating, or PCV system sucking in too much oil. If it doesn't burn that much with conventional oil, I would stick with that. If it does, you have a bad motor issue.

SOURCE: We have a 90 Quattro V8. Last summer I changed

Your V8 Audi has two necessary sensors that malfunction due to their placement in extreme heat on the lower left side of the engine just inside of the header/down pipe connection. They read the flywheel position for the engines computer ECU. The reference sensor is always suspect, but the speed sensor may need to be changed, as well. The wire connectors to the sensors that sit above the FL suspension can be tested, or just replace both sensors to get some quality time with your V8.