Locating Fuel Pressure Check Points In Your 240 Volvo

If you want to check the fuel pressure on a 240 Volvo, you can use a fuel pressure gauge. The factory method is to use a banjo fitting between the hard and flexible fuel lines. You can also use a schrader valve, although some Volvo 240s don't have one. The fuel pressure should be between 28 and 43 PSI.

No Schrader valve in the fuel system of Volvo 240s

If you are looking to check the fuel pressure on your Volvo 240, you may be disappointed to learn that there is no Schrader valve in the fuel system of Volvo 240s. Schrader valves are usually found in the fuel systems of some cars, making it easy to check fuel pressure.

However, there are other ways to go about testing the fuel pressure on your Volvo 240. Here is a step-by-step guide to help you through the process:

Step 1: Move Your Car to a Safe Location

First, it is important to prioritise safety. Move your Volvo 240 out of the garage and away from any sources of ignition. This will reduce the risk of any accidents during the testing process.

Step 2: Prepare the Fuel Line

Wrap the fuel line connection at the fuel rail with rags. This will help catch any fuel that may leak out during the testing process and minimise the risk of spills.

Step 3: Loosen the Fuel Line Fitting

Use the appropriate tools to carefully loosen the fitting on the fuel line. This will allow you to access the fuel system and perform the necessary tests.

Step 4: Use a Fuel Pressure Gauge

To check the fuel pressure, you will need to use a fuel pressure gauge. You can purchase or rent one from an automotive store or a specialised rental service. Ensure that the gauge you use is compatible with your Volvo 240's fuel system.

Step 5: Connect the Fuel Pressure Gauge

With the necessary precautions in place, carefully connect the fuel pressure gauge to the fuel line. Follow the instructions provided with the gauge for proper connection.

Step 6: Start the Car and Take Readings

Once the gauge is connected, start your Volvo 240 and take fuel pressure readings. The factory-specified fuel pressure for the Volvo 240 is between 35 psi at idle and 43 psi at wide-open throttle.

Step 7: Check for Leaks

After taking the necessary readings, remember to check for any leaks in the fuel system before turning off your car. This will help ensure that there are no fuel spills or potential safety hazards.

By following these steps, you can safely and effectively check the fuel pressure on your Volvo 240, even in the absence of a Schrader valve. Remember always to put safety first when working on your vehicle and refer to a qualified mechanic if you have any concerns or difficulties during the process.

Check the fuel pressure regulator

To check the fuel pressure regulator on a Volvo 240, you will need to locate the regulator itself. It is located on the fuel rail, and is a small, round component with a vacuum line attached.

You can then perform a sniff test to check for fuel in the vacuum line. If there is fuel in the line, the diaphragm has ruptured and the regulator will need to be replaced.

You can also check the fuel pressure with a fuel pressure gauge. The factory method for testing fuel pressure on a Volvo 240 is to use a banjo fitting between the hard and flexible fuel lines. The pressure should vary from 35 psi at idle to 43 psi at wide-open throttle.

If you are experiencing problems with your Volvo 240's fuel pressure regulator, there are a few things to look out for. The engine may run rough and stumble, or the car may struggle to start after ignition. The engine may also stall shortly after starting, and the fuel pump may become noisy. A bad fuel pressure regulator can also result in fouled spark plugs and decreased fuel mileage.

If you are having trouble starting your Volvo 240, it is recommended to check for fault codes using the On-Board Diagnostic (OBD) in the engine compartment. This can help to identify any issues and narrow down the possible causes of the problem.

The pressure should vary from 35 psi at idle to 43 psi wide-open throttle

To check the fuel pressure on a 240 Volvo, you will need to use a banjo fitting between the hard and flexible fuel lines. The pressure should vary from 35 psi at idle to 43 psi wide-open throttle. This means that the fuel pressure will increase as you accelerate.

It is important to note that opening the fuel line can be dangerous. Therefore, it is recommended that you connect everything, including the pressure gauge, and jumper fuses 4 and 6 to run both pumps before starting the car. This will allow you to check for any leaks before turning on the engine.

Additionally, it is advisable to move the car out of the garage and away from any sources of ignition. You can wrap the fuel line connection with rags at the fuel rail and loosen the fitting if necessary.

By following these steps and paying close attention to the fuel pressure readings, you can safely and effectively check the fuel pressure on your 240 Volvo.

The cold start injector, L jet Bosch is 30- 50psi

The cold start injector is a component of the Bosch K-Jetronic fuel injection system, which was introduced in the 1970s and used in various cars, including some Volvo models. This system is mechanical and relies on fuel pressure and pressure differentials to function.

The cold start injector in the K-Jetronic system is designed to work in conjunction with the thermo-time switch. It adds extra fuel when the engine is cranking over during a cold start, with an operating voltage derived from the starter solenoid. The cold start injector will spray fuel for no more than 8 seconds to prevent flooding, and only when the engine temperature is cold.

The Bosch L-Jetronic fuel injection system, on the other hand, was introduced later in 1974 and used in various European cars in the 1980s. This system measures air flow into the engine using a moving vane called the volume air flow sensor (VAF) to determine the amount of fuel to inject. It is an analogue fuel injection system, and the 'L' stands for 'luft', which means 'air' in German.

While both the K-Jetronic and L-Jetronic systems are fuel injection technologies developed by Bosch, they have distinct differences. The K-Jetronic system is mechanical and relies on fuel pressure and pressure differentials, while the L-Jetronic system uses analogue circuitry and measures air flow with a volume air flow sensor.

The specified fuel pressure range of 30-50 psi aligns with the operating parameters of the K-Jetronic system. As mentioned earlier, the K-Jetronic system pressurises fuel up to approximately 5 bar (73.5 psi), which overlaps with the given range. Therefore, it is likely that the reference to the cold start injector and the specified fuel pressure range of 30-50 psi is related to the Bosch K-Jetronic fuel injection system.

The in-tank pump is a helper pump for the main fuel pump

The fuel pressure on a Volvo 240 can be tested by hooking up a pressure gauge between the hard and flexible fuel line. The pressure should ideally vary from 35 psi at idle to 43 psi wide-open throttle.

To test the fuel pressure, it is recommended to first jumper fuses 4 and 6 to run both pumps and check for leaks before starting the car. This is because opening the fuel line can be dangerous. It is also important to move the car out of the garage and away from any sources of ignition before performing the test.

Some Volvo 240 owners have reported issues with stalling after testing and installing a fuel pressure gauge. In one case, the problem was potentially caused by a faulty MAF sensor, while in another case, the issue was resolved by simply cleaning the battery terminals and adding water to the battery.

Frequently asked questions