Hooking Up Fuel Pressure Tester: The Right Spot For Testing

When it comes to testing fuel pressure, there are a variety of options available for different car models. For instance, the S&G Tool Aid SGT-33865 CIS K-Jetronic Fuel Injection Tester is suitable for European cars and Volkswagen models assembled in the US that are equipped with the Bosch C.I.S. K-Jetronic Fuel Injection System. This tester comes with a gauge that measures 2.5 in diameter and has a dual scale of 100 PSI and 7 BAR. It also includes a plastic moulded storage case, adapters, an adapter application chart, hook-up instructions and a parts schematic drawing.

Another option is the Fuel Injection Gauge Pressure Tester Test Kit Universal Car System Pump Tool Set available on eBay. However, some users have noted that this kit did not have the correct fittings, and they had to cut up an old fuel injector pipe to make it work.

For those with a Porsche, the Pelican Parts CIS testing kit has been recommended by users on the Rennlist forum. This kit comes with all the correct fittings and can be used to tweak the pressure adjustment on the FD.

Additionally, for Mercedes-Benz owners, the Bosch CIS Fuel Injection Pressure Tester w/ Extras is a popular choice. This kit includes a six-part video series that provides instructions on how to hook up the gauge, run the fuel pumps and complete the test. It is suitable for both K-jetronic and KE-jetronic 6 and 8-cylinder CIS-injected engines from 1976 to 1991.

Lastly, for those on a budget, there are some cheaper alternatives available on Amazon and eBay, although these may require additional adapters to work with your specific vehicle.

How to hook up a fuel pressure tester to a CIS fuel-injected Mercedes

If you own a CIS fuel-injected Mercedes, a pressure tester is essential for maintenance and repairs. Here is a step-by-step guide on how to hook up a fuel pressure tester to your CIS fuel-injected Mercedes:

Before You Begin:

Firstly, ensure that your Mercedes is a compatible model. The fuel pressure testers and video guides mentioned in this response are designed for Mercedes with gasoline fuel-injected 4, 6, and 8-cylinder engines from 1976 to 1993. This includes the 350, 450, and 280 engines in the R107, W116, W123, and early W126 models.

Next, you will need to source or purchase a fuel pressure tester kit. There are various options available, and some are model-specific:

• The Bosch CIS Fuel Injection Pressure Tester w/ Extras: This kit includes Kent's tester and a six-part video series that guides you through the process of hooking up the tester and performing fuel flow and pressure tests.
• CIS Fuel Injection Pressure Tester Partial "Short" D.I.Y Build Kit: This kit allows you to build your own accurate tester at a lower cost. It includes a quality liquid-filled 160 psi gauge, brass adapters, a CIS-specific machined short fitting, sealing rings, a fuel pump relay jumper wire, and a super-thin 14mm combination wrench. However, it does not include instructions on hooking up the tester to your engine, which need to be purchased separately.
• Fuel Injection Gauge Pressure Tester Test Kit Universal Car System Pump Tool Set: This universal kit is available on eBay and can be modified to work with your Mercedes, as some fittings may not be compatible.

Once you have acquired the necessary kit, follow these steps:

• Review the instructions and video guides that come with your chosen kit. As different kits may have varying components and procedures, it is essential to refer to the specific instructions provided.
• Prepare your Mercedes by locating the fuel distributor and ensuring you have the correct fittings to connect the tester to your engine.
• Connect the fuel pressure tester to your Mercedes' fuel system, ensuring all fittings are secure and tight to prevent fuel leaks.
• With the tester hooked up, follow the instructions to run the fuel pumps and complete the fuel pressure test.
• After the test is finished, safely depressurize the system and remove the tester from the engine, again being cautious of any fuel leaks.

By following these steps and using the appropriate kit, you can successfully hook up a fuel pressure tester to your CIS fuel-injected Mercedes and perform the necessary fuel system diagnostics and maintenance.

How to hook up a fuel pressure tester to a CIS Porsche

To hook up a fuel pressure tester to a CIS Porsche, follow these steps:

Firstly, ensure you have the correct fuel pressure tester kit. Some kits may not have the correct fittings for your Porsche, so it is important to check before you begin. You may need to source additional fittings or adapters if your kit is missing any of the required components.

Once you have your kit, the first step is to relieve the fuel system pressure and make sure the fuel filter is not clogged. If it is, replace it. Then, clean any dirt off the fuel distributor cap.

Now, you can begin to hook up the tester. Refer to the typical CIS hookup diagram and connect the tester between the fuel distributor and the control pressure regulator. The hose without the flow control valve should be connected to the centre of the fuel distributor, while the hose with the valve should be connected to the hose removed from the fuel distributor or directly to the control pressure regulator. Be cautious when tightening any adapters with O-rings to avoid damage.

In some cases, you may need to piggyback adapters to get the right combination of threads for the connections. Once everything is connected, reactivate the fuel pump and start the engine, being sure to check for any leaks.

Next, you need to remove air from the system. If your tester has a release valve under the gauge, wrap a rag over the valve and depress the button until the air is released. Do not do this over a hot engine or manifold. If your tester has a bleed-off valve, put the end of the valve tubing into a fuel container and bleed the fuel until the air is removed.

If your tester doesn't have either of these features, position the gauge downward as far as the hoses will allow, with the gauge below the hoses and control valve. Operate the fuel pump with the engine off and open and close the control valve at least five times, ensuring that the valve is in the off and on position for at least 12 seconds.

Now, you can read the gauge to check the pressure. If the Cold Control Pressure is not correct, the warm-up regulator may be faulty. If the pressure is okay, you can proceed with the remaining pressure checks.

Remember to always exercise caution when working with fuel and ensure you have adequate ventilation. It is also recommended to have a fire extinguisher readily available as a safety precaution.

How to hook up a fuel pressure tester to a CIS Volkswagen

To hook up a fuel pressure tester to a CIS Volkswagen, follow these steps:

Firstly, ensure you have a suitable fuel pressure tester kit. Some options include the CTA3420, S&G33865, TU-447 OTC 6550, or a DIY option using spare fuel system components. The kit should include a gauge that can register 100 psi, hoses, and fittings that are compatible with your Volkswagen's fuel system.

Once you have the necessary equipment, locate the fuel distributor and the cold start valve. The tester will need to be hooked up between these two components. You may need to use a banjo fitting or a T-fitting with a flex hose to make the connection. Ensure that all connections are secure and tight to prevent fuel leaks.

If your fuel pressure tester requires a Schrader valve, you may need to drill out the centre of your test port plug and tap it for a permanent Schrader valve installation. This will allow you to hook up the pressure tester directly to this new port.

Before running the fuel pump and completing the test, ensure that you have depressurised the system and followed any necessary safety procedures. Refer to your Volkswagen's manual or a trusted mechanic for specific instructions on depressurising the fuel system.

Finally, run the fuel pump and complete the fuel pressure test, following the instructions provided with your fuel pressure tester kit. This may involve running the fuel pumps, reading the control pressure, and interpreting the test results.

It is important to note that working with fuel systems can be dangerous, and it is recommended to seek professional assistance if you are unsure about any part of the process.

How to hook up a fuel pressure tester to a CIS K-Jetronic system

To hook up a fuel pressure tester to a CIS K-Jetronic system, you will need a suitable pressure tester kit, such as the Bosch CIS Fuel Injection Pressure Tester or the Tool Aid 33865 C.I.S. K-Jetronic Fuel Injection Tester. These kits come with instructions and are designed specifically for fuel flow and fuel pressure testing on Bosch K-jetronic and KE-jetronic 6 and 8-cylinder CIS-injected engines.

• Park your car on a level surface and engage the parking brake. Allow the engine to cool down if it has been running recently.
• Locate the fuel pump relay in the engine bay. It is usually located in a fuse box or mounted on a fender wall.
• Disconnect the electrical connector from the fuel pump relay. This will prevent the fuel pump from activating during the testing process.
• Locate the fuel distributor, which is typically found near the fuel injectors.
• Identify the test port on the fuel distributor. This is usually a small fitting or valve with a threaded connection.
• Connect one end of the pressure tester hose to the test port. You may need an adapter or a reducing bushing to make a secure connection.
• Connect the other end of the pressure tester hose to the fuel pressure gauge provided with your kit.
• Start the engine and allow it to reach normal operating temperature.
• Observe the fuel pressure gauge to get a reading of the system pressure. Compare this reading to the specifications for your specific vehicle.
• If you need to perform further tests, such as checking the lower chamber pressure, refer to a repair manual or seek guidance from a qualified mechanic.

It is important to follow all safety precautions when working on a fuel system. Ensure the engine is off and cooled down before removing any fuel lines or components. Always wear protective gear, including gloves and eye protection. Work in a well-ventilated area to avoid inhaling fumes.

Additionally, if you are not confident in performing this task, it is recommended to consult a professional mechanic or seek guidance from a qualified technician.

How to hook up a fuel pressure tester to a CIS KE-Jetronic system

To hook up a fuel pressure tester to a CIS KE-Jetronic system, follow these steps:

Firstly, ensure you have the correct equipment. A fuel pressure tester kit is required, and there are several available on the market, such as the Bosch CIS Fuel Injection Pressure Tester, which is specifically designed for Mercedes vehicles with Bosch K-Jetronic and KE-Jetronic engines from 1976 to 1991. This kit includes a six-part video series that provides instructions on how to hook up the tester and perform the necessary tests.

Now, for the hook-up process:

• Remove the threaded pipe plug from the test port in the lower chamber of the fuel distributor.
• Connect the fuel pressure gauge line to the test port in the lower chamber of the fuel distributor. Use an M12 X 1.5/M8 X 1 Reducing Bushing to connect the hose to the chamber port.
• Remove the fuel supply line for the cold start valve from the top of the fuel distributor.
• Attach the pressure gauge line to the cold start fitting on the fuel distributor's upper chamber.

It is important to note that the system pressure is checked with the engine off, and engine temperature does not affect the system pressure test.

By following these steps and using the appropriate tools, you can successfully hook up a fuel pressure tester to a CIS KE-Jetronic system.

Frequently asked questions