Auto Problem

I have a 2000 Audi with 155,000 miles. when I start the vehicle with the outside temperature below freezing, there is a strong smell of gas, and the car does not want to shift upwards. It resists moving forward, with the transmission seeming to

“vibrate.” When the weather goes above 32 degrees the car shifts and runs beautifully. Any ideas?

You didn’t tell us whether this car has a manual transmission or an automatic trans, but I am going to guess that it is automatic. Based on that premise, two questions come to mind:

Is the level of your transmission fluid at the full mark on its dipstick?
Can you tell us when the transmission fluid and filter were last changed?

As to the gas smell, that could simply be from the car runnng on a very much enriched fuel/air mix until it warms up sufficiently in cold weather. From here it is difficult to assess the odor.

The car has a Tiptronic transmission. (Auto cna be driven like a stick) There is no transmission dipstick, it is a sealed system.

Well, obviously that makes it difficult or impossible for the average owner to check it. When was the transmission last serviced?

Maybe a year ago.

Have the fluid level checked, it can be done, its simply a bolt removed and filled until the tranny overflows which means full.

There can be a strong smell of gasoline from the tail pipe if the engine is running too rich. The raw gasoline will pass right through the cold catalytic converter. This could be caused by a coolant temperature sensor sending a super cold signal to the engine computer, or a wiring short.
A dirty MAF (Mass Air Flow) sensor and/or dirty throttle bore/throttle plate can also be players. They are, fairly, easy to clean with MAF cleaner, and throttle body cleaner. While in the engine intake, change the air filter.