Welcome to another Payday 2 guide! Big oil can be quite a complicated heist. It is only available as pro job so there is not much room for error. This biggest issue you will encounter is finding the correct fusion engine in Day 2. There are always 12 different fusion engines and you can only test one engine at a time. Meaning each time you pick the wrong fusion engine you will have to survive longer!

Finding the information.

To solve the puzzle of finding the correct engine the player must find two different notes and reach a value on a computer. The content of these 3 items is randomized and will determine which engine is correct.

Finding the right engine requires you to know

  • The correct gas color
  • The number of wires connected
  • The bar value

There are always 12 engines to choose from and they will always be in the same position. It is the color, number of wires and bar value that is randomized.


If you want an easy time then here is a nice calculator you can use

Obviously most of you will want to figure this stuff out for yourselves. So keep on reading!

Step 1: Finding the correct gas canister color

Finding the correct gas canister color is a two step process

1A: Find the note with gas type

Throughout the map several notes will spawn. These notes contains clue for finding the correct engine in Big Oil. The first note lists a type of gas. This will either be Helium, Deuterium or Nitrogen.


In this example the note contains the word Helium. Remember this.

1A: color references

In the lab, located in the basement, there will be a reference between gas type and gas canister color. This reference will always be the same and can be safely memorized.


There are 3 types of gasses listed on the board;

  • Nitrogen (yellow)
  • Deterium (blue)
  • Helium (green)

In my example the note listed Helium meaning we now know we will need a blue gas canister.

Step 2: Finding the number of wires

The second variable is the number of cables connected to the gas canister. The information will again be displayed on a note.

a Find the note that lists the number of wires

Throughout the map there are various spawns that may contain the note we are looking for. For more information on note spawns please checkout the following guide: .

We are looking for a note that either says H, 2x H or 3x H. The number references too the number of wires connected

  • H:  1 wire
  • 2x H: 2 wires
  • 3x H: 3 wires

In this example 2x H means we have to find a canister with 2 cables.

b Find the gas canister with the correct number of wires

Combining the gas canister color and number of wires means you can exclude most of the available fusion engines.

This example has two wires (2 x H) are connected the green canister (Helium).

Step 3: Find the correct bar value

IFollowing step 1 and 2 it is likely you will have only one engine left. However there are a few situations where there are multiple candidates. This happens when you get 2H or 3H.

  • Deterium 3H= engine #9 or engine #12
  • Nitrogen 3H= engine #8 or engine #11
  • Helium 2H=engine #3 or engine #6
  • Helium 3H= engine #7 or engine #10

The final piece of the puzzle is finding the correct bar value

a Find the computer

Inside the lab the a computer will spawn somewhere.

b read the computer display

Inspecting the display will show us a psi value. In this case it is equal or larger too 5783 psi. It can also be =, <=, < or >.

c Calculate the Bar

For some reason payday 2 requires us to have some knowledge of physics. To covert Psi to bar you will need to know that 1 psi = 0.0689475729 bar.  Basically you can device by 10 and multiply by 7.

Because the display is always listing 5783 or 5812 I can give you the values

  • 5783 psi = 398 bar
  • 5812 psi = 400 bar

Note that at some I did encounter a note that listed I should use 0.8xx. Maybe someone can confirm this for me.

d find the engine with the correct bar

Each engine will have a BAR meter. Simple read the display and find the BAR that follow the correct rule

In this case this engine would be correct for:

  • =400 bar
  • =>400 bar
  • =<400 bar

GameplayInside recommends gaming on: