Grand Theft Auto III is a game with many Glitches and Errors which can be used as ways to affect the gameplay, in most cases, making the game easier to complete. Here is a list of glitches, if you have any to add, feel free to share them below!
Walking above the Porter Tunnel Glitch
One method of reaching Staunton Island and Shoreside Vale before they're unlocked is using the Walking above the Porter Tunnel Glitch. There are two possible ways of doing this glitch - both will involve the top, concrete wall of Portel Tunnel. One way is to park the car right along the edge of the wall, in line with the tunnel and exit, and the other way is to reverse the vehicle off of the platform while facing east and exit as the door starts going over. When the player exits the vehicle, they will fall through the sea and into Blue Hell, but will land on top of the tunnel. The player can then walk along the tunnel, then jump into Blue Hell at the Staunton Island or Shoreside Vale end, so that the player can get teleported above the surface.
Walking Above The Subway Tunnel Glitch
This glitch can be performed at the subway in Shoreside Vale at the airport. When the train arrives to the platform, take the very last door of the train. Enter the train and then get out again. You will automatically get teleported above the platform, standing above Blue Hell and you will see the tunnel. Jumping into Blue Hell will make you respawn on the surface of Shoreside Vale.
Rhino Spawn Glitch
If you spawn a Rhino (using the cheat code) anywhere in the city, a second one will spawn in the middle of the street at Liberty Campus around the corner from the Staunton Island Safehouse.
Taxi Driver Glitch
The player can transport people in any car besides the Taxi or Cabbie by executing the following glitch. Enter a taxi cab, and press and hold the side mission button. Keep holding the button and exit the cab. Then enter the car to whichever one the player desires (except for other vehicles with side missions). Once in the new car, release the sub-mission button and the Taxi mission will start.
Crusher Glitch (Making a Vehicle Dent Proof)
You can make any vehicle (that the crusher will accept) Damage Proof by starting ‘Taxi Driver’ (you can use the above glitch), collecting a passenger near the crusher and then park car near the crusher like in the video linked. Then Press the 'Look behind' button and without releasing it, exit from the car. Enter the vehicle as you see the grabber coming down (still keep the ‘Look Behind’ button pressed), if done correctly, you should pull the passenger out of the car. Once in the car, release the look behind button and you and the car should fall back to the ground, ending the side mission 'Taxi Driver'. Your car is now a ghost and can drive through anything, DO NOT EXIT THE CAR as you will not be able to re-enter it. As a ghost, the car will periodically get larger and ruin the handling, drive through 'blue hell' and it will respawn you and restore the cars default size and handling (it will still be a ghost).
To make the vehicle dent proof, simply drive it into your garage, exit the vehicle and leave the garage.
This is also a good trick to get to other islands early as while in Ghost mode, you can drive through the Panlantic signs in the tunnel.
Pause Trick (Vigilante)
Whenever you are on a Vigilante mission, get near the target car and pause the game, entering the menu screen. Immediately once you resume playing the criminal on the car will stop and proceed his/her "getaway" on foot, being much easier to kill.
"Killer Look" Glitch
While you are on foot, if there is anybody trapped under a car and you use the first person view (just look around a little bit), they will die instantly. The death will not be added to Stats Menu. This also happens if the pedestrian is trapped under the car and the player starts a mission.
Tunnel Gang Reproduction
Inside the narrow tunnel near 8-Balls Bomb Shop that runs beneath St. Mark's, there are 4 pedestrians wielding Molotovs. Drive a Bobcat into the tunnel and stop so you are in view of the gang. Get out of the Bobcat, jump on its hood, and walk up to its roof and jump back down onto its hood, 4 more of these pedestrians will spawn in the same spots. The game will freeze after at least 40 have spawned.
Joeys Garage Glitch (1)
Drive a car into the left garage door. Run on the left corner between the door and the garage. After a few seconds, you will be inside the garage.
Joeys Garage Glitch (2)
Park a Linerunner besides the back door and jump onto the very top of it so you should be halfway through the wall, drop a grenade (make sure you have full health) and you should appear on top.
To get your accuracy over 100% you have to shoot with M16. When you shoot with M16 the bullets you shoot off the gun won't count, but those that hit the target add up to the total quantity.
Breaking out of the first mission
This is a glitch which requires a mission failure - This glitch results in you being able to explore LC in the prison outfit before Give Me Liberty has begun. To do this, when 'Give Me Liberty' starts, you need to somehow flip 8 Ball and the Kuruma over (Easiest by letting fall off of something) hoping it will fail the mission - The moment the 'Mission Failed' Message comes up you need to jump, if done successfully you just appear on the bridge in free roam, you will only be able to walk forward at this point - Jumping will enable you to walk in any direction
The Portland Safehouse is locked but it can be unlocked by using the Crusher Glitch and exiting the ghost vehicle when it is inside the safehouse causing the save menu to appear, just cancel it (or save if you wish) and the door will fling open.
There will be no specific mission marker or a radar icon for "Give Me Liberty" mission, so to trigger it, Claude has to be standing in a specific place. I have used my super experienced Art Skills below to show the location of the invisible mission trigger point, highlighted in blue. Use the radar from the screenshot to navigate yourself to this point.
Porter Tunnel Glitch
If the player is driving thorugh the tunnel, particularly through the Portland and Shoreside sections of the tunnel, the player may spot cars such as the TOYZ van which appear to be hovering with their lower section (the wheels) inside the tunnel and their top section outside the tunnel.
Purple Nines Glitch
If you start a new game with Rumble completed on another save file, the Purple Nines will not spawn as they permanently disappear after that mission. This will make it impossible to complete Uzi Money and subsequent D-Ice missions, as killing randomly spawned Nines is the sole objective of the mission.
Disappearing vehicle glitch
The Disappearing Vehicle glitch is prevalent in all of the 3D era games and occasionaly in HD era games. If the player parks a car near any mission marker, and then walks into the marker to trigger the mission cutscene and starts the mission, there is a high chance that the vehicle he parked will have disappeared after the cutscene.
Walking in walls
Some walls in the game have weak spots as shown here making you able to walk into them.
Driving Through walls
Some walls/points across LC have weak spots allowing you to reverse vehicles into Blue Hell. If done at the right spots, you can reverse vehicles on to the top of the subway/tunnel allowing you to get them to other islands easily.
Use lol232's Unique Vehicle Guide for more information: http://gtaforums.com...-vehicle-guide/
Wear Prison Uniform
If you load a save game as soon as you start a new game, the game can occasionally glitch to make Claude wear the prison outfit from the introduction.
Weapon Pickup Respawn Glitch
Once you have weapon spawns at your hideout (obtained by collecting hidden packages), go to your safe hour, collect the weapons and walk into the safehouse's garage and continue walking all the way until you hit the back and the camera swings around. Once that has happened, just walk outside of the garage and the weapons should have respawed!
-Thanks to TheMantisDied for submitting this glitch!
This glitches list is incomplete, some glitches have most likely been missed out by mistake. If you have any more glitches to share, post them below!