So, I've been pausing every time I want to enter the max health and armor code to repair my vehicle, but it gets kind of annoying to have to pause, wait for the menu to load, hit X to view the map, then enter the code and hit start, but I figured out a better way.
As you may know, the code to get max health and armor has a triangle in it which means you'll get out of your car if you try to enter the code while driving... who ever came up with that code is an idiot, but I've found a way around it so that you don't have to pause the game.
1. Make sure you're in your car and you have your pistol selected as your weapon.
2. Get out of your car.
3. Press triangle to start climbing into your car
4. While you're climing into your car, quickly enter the code (circle, L1, triangle, R2, x, right, square, L1, L1, L1)