Press R2, R1, Triangle, X, L2, L1, Up, Down during game play. A message will confirm correct code entry. Some pedestrians will throw bombs or shoot at you if you steal their car. Note: Saving the game will make the effects of this code permanent.
All weapons
Press R2(2), L1, R2, Left, Down, Right, Up, Left, Down, Right, Up during game play. A message will confirm correct code entry. Repeat this code for more ammunition. To get unlimited ammunition, enable the "All weapons" code continuously until whatever you want is at 9999 shots. The next time your clip runs out, it will reload automatically but the magazine (9999) will stay the same. Note: If you are busted your weapons will disappear and this code will have to be repeated.
Better driving skills
Press R1, L1, R2, L1, Left, R1(2), Triangle during game play. A message will confirm correct code entry. Press L3 or R3 to jump while driving. Note: Saving the game will make it so your car will never tip. Also every car will have hydraulics which will enable it jump 15 feet in the air over other cars. After this code is enabled, any time you roll your car, press Square + X to flip back over. This will work as long as your car is not on its roof.
Destroy all cars
Press L2, R2, L1, R1, L2, R2, Triangle, Square, Circle, Triangle, L2, L1. A message will confirm correct code entry.
Different costume
Press Right, Down, Left, Up, L1, L2, Up, Left, Down, Right during game play. A message will confirm correct code entry. Note: This code can also be used to get invisible weapons. First, have a weapon in your inventory. Then, enable the "Different costume" code. Once you have changed costumes, you should be holding a weapon but you cannot see it. Note: Pressing R2 or L2 to change weapons will change it back to a visible weapon again.
Faster game play
Press Triangle, Up, Right, Down, Square, L1, L2 during game play. A message will confirm correct code entry. Repeat this code to increase its effect.
Flying car (low gravity)
Press Right, R2, Circle, R1, L2, Down, L1, R1 during game play. A message will confirm correct code entry. Accelerate and press Up to take off.
Fog
Press L1, L2, R1, R2(2), R1, L2, X during game play. A message will confirm correct code entry.
Full armor
Press R2(2), L1, L2, Left, Down, Right, Up, Left, Down, Right, Up during game play. A message will confirm correct code entry.
Full health
Press R2(2), L1, R1, Left, Down, Right, Up, Left, Down, Right, Up during game play. A message will confirm correct code entry. Note: If this code is enabled during a mission where there is damage on your car, the meter will be reset to zero. If your vehicle is on fire, enable the "Full health" code to extinguish it. This code also repairs your car. You cannot see the repairs, but it will act like a new car. If on a mission where you need to have a mint condition car, sometimes enabling the "Full health" code will fulfill the mint condition requirements.
Higher wanted level
Press R2(2), L1, R2, Left, Right, Left, Right, Left during game play. A message will confirm correct code entry. Note: Saving the game will make the effects of this code permanent.
Increased gore
Press Square, L1, Circle, Down, L1, R1, Triangle, Right, L1, X during game play. No confirmation message will appear. You can shoot off pedestrians' arms, legs, and heads with some weapons (sniper rifle, assault rifle, explosives) with an increase in the overall amount of bloodleft behind. Note: Saving the game will make the effects of this code permanent.
Invisible cars
Press L1(2), Square, R2, Triangle, L1, Triangle during game play. A message will confirm correct code entry. Only your vehicle's wheels will be visible.
No wanted level
Press R2(2), L1, R2, Up, Down, Up, Down, Up, Down during game play. A message will confirm correct code entry. Note: Saving the game will make the effects of this code permanent.
Normal weather
Press L1, L2, R1, R2(2), R1, L2, Triangle during game play. A message will confirm correct code entry.
Overcast skies
Press L1, L2, R1, R2(2), R1, L2, Square during game play. A message will confirm correct code entry.
Pedestrians attack you
Press Down, Up, Left, Up, X, R1, R2, L1, L2 during game play. A message will confirm correct code entry. Note: Saving the game will make the effects of this code permanent.
Pedestrians riot
Press Down, Up, Left, Up, X, R1, R2, L2, L1 during game play. A message will confirm correct code entry. Note: Saving the game will make the effects of this code permanent.
Portland: Get to Staunton Island early
Use the following trick to get to Staunton Island before the bridge is fixed and before the subway is open. Go to the bridge to Staunton Island. Go past where the blockage cones are located, to basically be on the bridge. Enable the "Flying car" code, then the "Tank" code. Make sure you are all the way back to get enough room to take off using the tank (as a plane). Start firing the cannon backwards and accelerate. Keep firing the cannon backwards, and just as you get to the edge where the bridge has been broken, you will take off. Try and get back on the ground. If done correctly you will now be on Staunton Island. Note: When you cross the bridge, the "Welcome To Staunton Island" screen will appear to confirm success. Note: You can use nearly any car, but the tank has a better ability to fly higher.
Steal an Ambulance from Sweeney Hospital. Go to the bridge and enable the "Better driving skills" code. Drive your ambulance on the road towards the bridge and press L3 just before the road starts to dip down. If done correctly, you should make it across, but your ambulance will probably tip over and explode. Make sure you are out of the way, then run into Staunton Island.
Note: When on Staunton Island you can not do any missions. When you die, you will be transported back to the hospital in Portland.
You can fly over to Staunton Island by enabling the "Tank" and "Flying car" codes after dropping off 8 Ball. However, only activate the "Tank" code when you have walked onto the broken bridge. You cannot save the game over in Staunton Island, and if you die or get arrested you will be transported back to Portland.
Enable the "Better driving skills" and the "Flying car" code after you drop 8-Ball off at the hideout. After you drop off Misty at the Luigis Sex Club Seven, go to the fire station and get the fire truck. Do not disable the codes. Instead, go to the bridge and jump the gates. Drive off the bridge slowly until there is a big shadow mark, then hit the gas. Once you start going in the air press the Up for about one second, then release. Keep doing this continuously. Once in Staunton Island you can easily go to the lift bridge to go to Shoreside Vale, however the lift bridge is more difficult than the Callahan Bridge.
Steal a Mafia Sentinel and go the Callahan Bridge. Aim the Sentinel towards the break in the bridge and floor it. The car will leap over the gap in the bridge.
Get a Banshee (one location is in the glass-windowed building next to 8-Ball's Bomb Shop) and go to the bridge that leads over to Staunton Island. Get on the edge of where the bridge starts, and drive up past the obstacles. Enable the "Flying car" code. Drive fast to get across the opening; start near the bottom of where the bridge starts. When you approach the opening, press Up to fly. Note: This must be timed correctly,
In the "Last Request" mission, it is possible to "maroon" the Japanese girl. To do this, look for the closest "island" when you pick her and Maria up. Get to the island and back the boat up a slope. You will hear crunching sounds. Experiment, and sooner or later she will drop off the boat and onto the island. From there, get to Staunton Island. You can cruise around and do everything else except take up any missions or side jobs. Kill Maria or the Japanese girl and the mission will end.
Rain
Press L1, L2, R1, R2(2), R1, L2, Circle during game play. A message will confirm correct code entry.
Slower game play
Press Triangle, Up, Right, Down, Square, R1, R2 during game play. A message will confirm correct code entry. Note: This also continues the effect of an adrenaline pill.
Speed up time
Press Circle(3), Square(5), L1, Triangle, Circle, Triangle during game play. A message will confirm correct code entry. Repeat this code to increase its effect.
Tank (Rhino)
Press Circle(6), R1, L2, L1, Triangle, Circle, Triangle during game play. A message will confirm correct code entry. The tank will appear in front of you. This may be repeated as many times as needed.