Project Summer car is an advanced mechanics mod for Project zomboid that adds a whole bunch of components to your engine.

Here is some details about them, this mods features and how to keep your car driving!


First: For a vehicle to be drivable for any length of time, it must have at least 30% oil condition. This means over 30% filled with motor oil. A vehicle may also have additional used oil in its oil pan, so either take a sample from the oil pan or use the 'smart oil indicator' feature and make sure your oil light isn't red before starting. Mouse over oil light to see oil quantity and condition.

Lack of oil will cause engine damage and seizure in short order.

Second, keep an eye on your battery indicator. If the battery light turns red while running, your alternator is not charging enough. Make sure your fan belt and alternator are in good condition to fix this. If its red with the engine off your battery is almost dead.

Third, If the temperature indicator lights up yellow you are boiling off coolant. Red means you are doing engine damage from overheating. Add water and/or antifreeze to the radiator to improve its cooling capacity and its thermal storage capacity. Make sure your fan belt and water pump are in good condition.

Motor oil is the life blood of the car. Its consumed in engines with poor piston/crank/cylinder head condition and may be contaminated with water if your head gasket fails.

It will leak out of your engine at low oil pan condition (<25%) or head gasket condition (<25%)

Piston/crank/cylinder head condition also determines how fast motor oil gets contaminated and turns into used motor oil.

Water and Antifreeze are used in the radiator to cool the engine. Without it, its completely ineffective. At high temps your coolant will boil off, cooling the engine slightly in the process. The temperature indicator will turn yellow to indicate this. At very high temps engine damage will occur and the temperature indicator will turn red to indicate this.

ATF is used in the transmission and power steering pump. Without it your transmission will slip and steering at low speed will be very slow.

The main engine parts are:

Crankshaft, Pistons, Spark plugs and Cylinder head: These all determine your cars horsepower and how easily it is to start. You can find upgraded sport and racing performance parts for these to further improve your cars horsepower. If any of these are at 0% your car will not run.

Head gasket: this seals your engine. If it gets very low condition your coolant and oil will start mixing with each other and leaking out the engine. Very important to keep this above 25%

Flywheel: this helps smooth out the torque of the motor between piston firings and is vital to starting and running the engine. Upgraded flywheels are lighter and allow you to rev up/down faster.

Starter: The little electric motor used to actually start the car. Without one of these your car isn't going to start.

Oil Pan: Without one of these your oil won't stay in the engine. If below 25% condition it will leak badly.

Oil Filter: The condition of this part reduce the speed that your motor turns motor oil into used motor oil. If its missing your engine will puke all the oil out in short order.

Fan Belt: Drives all your accessories. If below 30% condition all the accessories will start to work less efficiently.

Alternator: Recharges your battery. if below 30% combined effectiveness the battery light will come on in your dash while the motor is running.

Air condition: Cools your cabin when you turn the HVAC controls below the midpoint.

Power steering pump: Without this your car will be very slow to steer at low speed. Requires ATF fluid to work.

Water pump: Required to move coolant (and hence heat) from the engine to radiator.


Radiator: Cools the engine. If badly damaged will leak coolant. If low on coolant it will be much less effective.

Brake Booster: this greatly improves your braking ability. Without it you'll have very little braking power.

Heater Core: Heats up your cabin when you turn the HVAC controls above the midpoint.

This mod has a ton of other misc features. I'll try to list them here:

Press V and select Change dash to change between the mods and vanillas dashboard. More dashboards coming soon!

Engine parts always get removed/installed if you attempt to do so. How long it takes, your chance of damage and how much damage will be done depends on your mechanic skill and difficulty of installing/removing the part. EXP is given based on the difficulty of the part and the condition of it when you finish installing/removing it.

Starting your car always uses battery power now. With a low condition battery it will take even more power to start the car. There are sandbox settings for charge rate and battery capacity!

If your windshield is broken and you drive in the rain, you'll get wet!

If your windows are down or broken, you'll get colder if you drive fast. Great if your air conditioner is broken on a hot day!

Click and hold on the key in the ignition to start the car! Goes great with 'Disable autostart on gas pedal'