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Fuel system clean save 20% to 60%

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Fuel system clean

What is a fuel system clean?

Petrol and diesel vehicles can get a build-up of dirt, grime and carbon deposits inside the fuel system. A fuel system clean is similar to a fuel injector clean except it’s a more powerful clean for the system. A fuel system clean will remove water and fuel deposits, clean and lubricate injectors, valves, rings, cylinder heads and combustion chambers. The throttle body and throttle plate/butterfly valve will typically be cleaned of dirt and grime at the same time.

A fuel system clean is carried out as a maintenance task or when a vehicle is running rough. The chemicals in the fuel system cleaner have a way of vanishing the nasties that can cause fuel system problems, but it’s not a magical cure for all fuel system problems. It can also help in removing contaminants and carbon build up in the fuel tank, fuel pump and fuel filter however it doesn’t eliminate the need to replace the fuel filter which still needs to be done at the specified time and kilometre interval.

How to tell if you need a fuel system clean

  • Poor vehicle performance
  • Rough idle or intermittent shudders
  • Doesn’t respond well on acceleration
  • Hard to start
  • Change in fuel consumption

How important is it to get a fuel system clean done?

Petrol and diesel engines run on fuel, and need the correct air-fuel ratio to provide optimal engine combustion - known as a clean burn. If that fuel supply is contaminated or isn’t flowing at the correct rate then it can foul the spark plugs, provide the incorrect quantity of fuel to the engine, produce an unclean burn and worst-case scenario, lead to engine failure. 

A clean fuel system is ideal for vehicle reliability and smoother driving.

Fuel system clean

How is a fuel system clean carried out

  • The fuel system cleaner container is connected to a vacuum hose 
  • The engine is started and kept running
  • The fuel system cleaner is gradually fed into the air intake through a valve and hose - too much can stall the engine, so the slower the better
  • Engine is left to run for a while
  • When all the cleaner has gone through the system the engine is stopped and the fuel system cleaner container and hose are disconnected
  • Vehicle will be test-driven - there will be smoke from the exhaust, how much will depend on how fast the cleaner was run through the engine

Some mechanics will also add fuel system cleaner into the fuel tank and in some cases the engine oil, this is to get a more thorough clean throughout the system. It will depend on the type of cleaner they are using. Ideally, the mechanic will also clean the throttle body.

The vehicle may run rough after a fuel system clean and blow smoke out of the exhaust, this should right itself after a short drive. If it continues then take it back to the mechanic.

How much does a fuel system clean cost?

A professional mechanic may take 30 mins to 2 hours to carry out a fuel system clean. The time depends on how thorough the clean is and how long it takes to run the cleaner through the system. 

If the fuel system clean is performed as a regular maintenance task then the cost won’t be too high, but if the vehicle has a history of performance issues, then more time may be needed to assess the fuel system. The cost can range from 10’s of dollars and move up into the hundreds to clean the fuel system.

If a vehicle has had the wrong fuel added to the fuel tank or someone vandalised the car by putting a foreign substance into the fuel tank and then driven, an entire fuel system clean will need to be carried out. The vehicle would need to be towed to a workshop and a mechanic would need to assess the damage and quote the repair based on the work involved.

Where can you get a fuel system clean?

A qualified mechanic can carry out a fuel system clean. They can do this in a workshop or a mobile mechanic can come to the car and carry out a fuel system clean. If you are looking for mechanics that do fuel system cleans AutoGuru offers a choice of mechanics with customer reviews to compare and book.