Locate the fuel test port on the fuel rail. The engine cover can be pulled up as it is held in place with four tabs and no screws.

Open the hood of your Mercedes-Benz. Remove the engine cover. 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 if the fuel pressure is withing range or not. If you suspect that your fuel pump is not working, you need to perform a fuel pressure test to verify.

If you need help diagnosing fuel problems on a diesel engine, check out this tutorial. In this tutorial, we 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 having 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.

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