c230 kompressor 2003 fuel system troubleshooting

C230 kompressor 2003 fuel system troubleshooting how to#

Remove the electrical connector from the fuel pump.

Locate the fuel pump, in most cases, under the rear seat.

How do you check if the fuel pump is getting power? This can be a damaged electrical wire issue or the Engine Control Unit not powering the fuel pump for various reasons. It is very common that, for various reasons, power is not going to the fuel pump. Next, we want to ensure power goes to the fuel pump. Let’s say you check the fuel pump fuse and relay, which are both good.

C230 kompressor 2003 fuel system troubleshooting how to#

You can either test the relay if you know how to or swap it with the same relay from a different system. Perform the following test before you replace the fuel pump.Ĭheck the fuel pump relay. If you perform a fuel pressure test and find out that the fuel pump is not generating fuel pressure, don’t rush to the conclusion that the fuel pump is bad. Test 3: Check the Voltage at the Fuel Pump

If the fuse is good, you must test the fuel pressure. The first thing that you should do is check the fuel pump fuse. The fuel pump may have failed if your Mercedes cranks but won’t start. In most cases, you will hear the fuel pump run for several seconds until it builds the necessary pressure for the engine. When you turn the ignition on, listen carefully to the rear seat ( near the fuel tank ). Test 1: Fuel Pump Hearing TestĪ simple way to check if the fuel pump is working is to turn the ignition to position II (all dash lights will turn on). Let’s look at the top fuel problems and how you can troubleshoot some of them. Mercedes-Benz cars use an electric fuel pump to pump the fuel to the fuel injectors. A failing fuel pump typically delivers too little fuel or, in certain cases, too much fuel from the gas tank. Under normal operation conditions, the fuel pump provides a constant fuel flow. Typically problems related to the fuel pump and fuel pressure include: Troubleshooting Mercedes Fuel Pump ProblemsĪ bad fuel pump can cause the engine no start condition or poor performance. *Note that under normal operation, the fuel pressure should build up as soon as you turn on the ignition before you even crank the engine. With vacuum hose disconnected: 54 – 61 PSI.You will notice that the fuel pressure didn’t change much when RPMs were kept constant at 4000, 2000, and idle, which is a good sign. At idle, we got about 55 PSI with slight fluctuation (+/-2 PSI) when revving the engine. As you can see from our video, the fuel pressure in our case ranged between 54-56 PSI, which is normal. Try starting the motor and get a fuel pressure reading. If you turn the ignition ON, the fuel pressure should build up before you even crank the engine. If you have difficulty finding your Mercedes’s fuel pressure port (Schrader valve), start from one of the fuel injectors and follow the fuel rail. Locate the fuel test port on the fuel rail. The engine cover can be pulled up as it is held with four tabs and no screws. Never carry this test if the engine is hot. Keep a fire extinguisher nearby in case of emergency. If fuel falls on hot engine parts, you may cause a fire. This test applies to Mercedes-Benz vehicles equipped with 4-cylinder, V6, V8 and V12 gasoline engines such as M112, M113, M119, M104 M272 and M273.īe extremely careful during this test procedure. The Actron CP7818 fuel tester works on most Mercedes-Benz and has the required Schrader valve required for MB cars. For this test, you will need a fuel pressure gauge. A fuel pressure check on your Mercedes-Benz will tell you whether the fuel pressure is within range. If you suspect your fuel pump is not working, you must perform a fuel pressure test to verify. If you need help diagnosing fuel problems on a diesel engine, check out this tutorial. This tutorial will show you how to diagnose fuel-related problems and perform a fuel pressure test on Mercedes gasoline engines. While fuel pump failure isn’t very common in MB cars, we have seen several Mercedes cars such as M元20, C-Class, and E-Class models have a fuel pump go bad as early as 120k miles. It pumps the gasoline from the fuel tank to the engine. The fuel pump is located in the fuel tank. The fuel pump plays a vital role in Mercedes-Benz cars.