Few Miata questions

So after the fiascos of October, this car has actually been quite good. It's fun to drive, gets 25MPG even though I drive everywhere at 5,000 RPM's, and it's comfy with the hardtop on. Anyways, there's still a few issues:

1. Oil consumption. This pig eats a quart every 800 miles! It's got 10W30 dino oil in it now. No consumption issues until I ran Royal Purple in it once. It's only had 1 oil change after that 10 mile fiasco. Anything I can do?

2. B. Freezing Oil - It's starting to get cold. Below freezing stuff. Any changes here? 5W30?

III. 3rd Brake light. Stupid thing has never worked. Considering how many F450's try to kill me every day, I would like to fix that. I already replaced the bulb and re-spliced the wires where they broke on the truck hinge. Ideas?

1. Engine racket. Probably related to 1. Sounds like 3 bolts and a rock being shooken in a coffee can. Runs sweet though! Keep ignoring it? (Mostly cold, but it never "shuts up" when hot. I've had mechanical cam V8's make less noise than this).

3rd brake light: I've found that the wire likes to break not only at the hinge, but further up and/or downstream. Get out the multimeter, and start probing until you find 12+V. Then, splice from there. Heck, I've spliced, checked for operation, driven to the inspection station, and had another break in the 2 miles between. Frustrating to say the least.

I do go to 5W30 in the winter.

Not sure on the other two questions, without hearing the car myself. Any idea where a quart is going in that 800 miles? CAS, valve cover gasket, rear main seal???

Out the exhaust for sure. It smokes on start up and while driving cold and/or hard.

Engine is clean as a button, no drips in driveway. I changed the CAS and o-ring, vc gasket, and all of the gaskets and seals on the nose of the motor when I did the timing belt.

Mine made a terrible engine racked that sounds similar to what your describing. I did some searching and found a lot of missing bolts on the heat-shield over the exhaust manifold. Replacing them nearly eliminated the noise (I can still get it to rattle a touch at certain RPM's).

Never even thought that the racket could possibly be outside the motor! Thanks Cap'n!

The rattling is most likely your exhaust shield. Clamp it, or remove it like some people do.

Welp, the shield is a rattling, but it's not all. Poor engine sounds like the gaps can be measured with a yardstick, but it runs so well! Meh, it's a 1.6. I'll run it until assplodes and then buy a lower mileage JY one for $200.

I do have to say that now that it's raining and freezing out, the open diff flipping SUCKS!!!