First problem, simply because you observe no obvious smoke, doesn't mean the engine isn't burning oil. If you can see that much smoke, your engine is definitely worn out!I have a 2005 Chrysler 300 cc with about 109k miles all highway.
Two problems I have
1- it eats up engine oil somehow, no smoke, no leaks and runs like a champ. Changed the PVC valve but still uses engine oil say about a quart a month. Dealer could not find a problem.
2- recently happened few times while stopped at a red light I felt bumped, looked behind me and no one there and sometimes while stopped with foot on brakes car shook a bit as if it was going to stall but never did.
Any ideas what can be causing this?
One mechanic suggested I check the brakes ??
Another suggested to look into transmission??
Given the mileage on the engine, the valve covers are probably seeping, but not enough to be obvious to the inexperienced observer. The valve guides & seals are also worn enough to allow oil to be drawn into the cylinders. Again, not enough to be seen normally. You may observe some gray smoke immediately on start-up. This dissipates quickly, but it is indication oil is leaking into the combustion chambers.
I will qualify the above information by stating, you failed to provide information on your monthly mileage, or how many miles you drive between oil changes. You only said the miles are highway miles. Any engine, even new ones, burn some oil. It's a machine, after all. An engine using a quart between NORMAL oil changes is not a indication of major problems in the engine. It all depend on the amount of heat generated during a particular operating period.
Unless you can find a reputable mechanic, that can ask you what your driving habits are, and you can provide him with the answers, a solid diagnosis cannot be made to determine if your engine is using oil excessively. It's a bit like going to your doctor.
If you want to determine if you have an issue with the oil usage, record the mileages and dates at which you change and add oil to the crankcase. Do that for at least 2 oil changes. Oil changes should be done every 3 thousand miles, or 3 months, whichever comes first. If you add oil between changes, add the exact same oil that was used at the last oil change.
NEVER MIX OILS WITH DIFFERENT MANUFACTURES!
You can use any oil, from any manufacturer,as long as it is the correct type recommended by Chrysler for your engine, AT OIL CHANGE! NOT BETWEEN!
The second issue, I can't provide a diagnosis given the information you provide. I'm sorry. I can only speculate, and that will not help you.
I would suggest you have the fuel filter changed, if it hasn't been done in the last 50,000 miles. Could easily be the problem!