Replacing S4 Fuel Pump Relay?

Answer The fuel pump relay on an Audi S4 is designed to control the voltage to the fuel pump. When the engine control module, or ECM, decides to turn on the fuel pump, it signals the fuel pump relay to se... Read More »

Top Q&A For: Replacing S4 Fuel Pump Relay

How to Remove Pressure From the Fuel System for Replacing the Fuel Pump?

The fuel system pressurizes fuel from the fuel tank to the engine. Fuel-injection systems meter the fuel injected for the cylinders by controlling the length of time the injectors are open. To inje... Read More »

Replacing a Fuel Pump?

All vehicles today incorporate a fuel pump located within the fuel tank. The fuel pump is cooled by fuel. The reasoning for this is simple--longevity and sound level are the main reasons. With the ... Read More »

What is Fuel Pump Relay?

A fuel pump relay is a switch to activate the fuel pump when a car engine is first turned on. Problems with a fuel pump relay can make it difficult or impossible to start the car.References:AA1Car:... Read More »

What Is a Fuel Pump Relay?

Almost all cars use some sort of relay to activate the fuel pump. Relays take the low-voltage current applied by a switch and use it to close the high voltage circuit required to run a connected d... Read More »