Well if it's only happening online it may be you are using driver aids in A Spec that the rooms you are going into don't allow so they are automatically disabled.
I also drive like a noob online. but I am a noob.
what I've been doing is pretty much sticking with one car and playing exclusively with no aids, in 500PP rooms.
After a while I got a little better but still never better than middle of the pack.
Someone that is a beginner to something is referred to as a noob/newbie. It's nothing to be ashamed of, it's just something someone is! I'm a noob a COD, so what?
Smooth is fast. Are you entering the corners smoothly and exiting smoothly, avoiding any abrupt movements? Are you using the WHOLE track to your advantage? You should enter the corner from the outside cut in close and exit the corner getting as close to the outside as possible. Practice doing this and you should be good to go. Have you ever rode with someone in a car and it's a jerky ride? They brake, accelerate, steer hard? You should imagine your the car driver and you don't want your passenger to experience this. Smooth braking, Acceleration, and most importantly, smooth STEERING. Remember, it's always better to overbrake while going into a corner and have to reapply throttle than to late brake and go off the track. You can't win a race at the first turn...
Just avoid oversteer/understeer by finding the apex and steering smoothly, not too sharp. And when getting out of a corner, don't use full throttle or you'll spin out.
If you are used to playing arcade racing games, then you should know that GT5 is nowhere near those. GT5 is a racing simulator that, well, simulates real-life physics. If you are using a hi-powered car and you press the throttle all the way coming out of a low-speed corner such as a hairpin, then you are definitely going to spin out, just like in real life.
What you need to do is be easy on the throttle. When you press the throttle (in your controller, the default is X), find how much pressure there is before the car starts to spin. You need to get a feel for the car. It's a bit hard at first, but once you get the hang of it, controlling the throttle will become second nature.
Made my day. 👍 ...the whole thing 
