Fuel Injector Cleaning Methods

Fuel Injector Cleaning Methods

Fuel Injector Cleaning and Flow Testing Service

photo: Bosch


Why “Off of the Car” fuel injector cleaning is the Best!

        Off of the car fuel injector cleaning and flow testing (where the injector is removed off of the engine) offers many advantages over other fuel system cleaning services.  It is the only reliable and accurate way to visually confirm “without a doubt” that your fuel injectors are truly clean and functioning properly.


In the Tank “Bottle” Cleaners:


  • The least expensive and easy.  Costs about $5 to $20 / bottle.  Good for periodic maintenance.


  • Not effective for solving existing fuel injection problems.  The cleaning agents are diluted too much in the gas tank to be effective for serious baked on varnish, gum, and carbon deposits. 
  • No way to know if any or all of the injectors have been properly cleaned.
  • Cannot identify leaking injectors, poor spray patterns, or flow volume problems.


On the Car “Fuel Rail” Cleaning:

       This is where a pressurized bottle of harsh cleaning solution (like BG 44K) is injected directly into the fuel rail to clean the injectors while the engine is running.  The engine actually runs entirely on the cleaning agent during this service.  The fuel pump is disabled during the service.


These “cleaning agents” are actually various mixtures of  kerosene and white spirits like paint thinner.          



  • More effective than in-the-tank method due to using an undiluted stronger cleaning solvent.
  • Also, the gas in the vehicles tank, fuel pump, fuel lines, fuel filter, and fuel pressure regulator are spared exposure to the harsh chemicals.


  • Higher risk of damage to the injectors, O2 sensors, valves, and catalytic converters.  This method often dislodges particles on the injectors’ micro filter, and can clog the injector’s valve. 
  • Expensive, usually well over $100 at most shops.
  • When done, you still do not know if the injectors are performing properly.
  • Badly clogged injectors may not pass enough solvent through during cleaning, and may not get thoroughly cleaned.
  • Some really baked on deposits can be really hard to remove even with a strong solvent.
  • If on the car fuel rail cleaning fails to restore injector performance you will have to remove the injectors anyway !!



Professional off the car fuel injector ultrasonic cleaning and flow testing:          



  • Each injector is tested for:  coil resistance, coil draw down (tests coil under electrical load), fuel leak down, fuel spray pattern, and fuel flow rate.
  • The ultrasonic cleaning solution we use is environmentally safe, biodegradable, and does not damage the metal or rubber components of the injector. The harsh solvents in bottled fuel injector cleaners can damage your fuel injectors and other fuel system components.
  • Our Fuel injector ultrasonic cleaning tanks use sonic pulses to ‘ blast ‘ the dirt and deposits off of the fuel injectors. This ultrasonic cleaning completely removes even the most stubborn baked on deposits from both the outside and the inside of the fuel injectors.
  • All replaceable parts are removed and new parts are installed:  upper and lower o-rings, micro filters, and pintle caps are replaced (when commercially available ). Note: a small number of filters and pintle caps are not commercially available, usually they do not actually need to be replaced and cleaning is sufficient.
  • The overall price is about the same as on-the-car fuel rail cleaning.
  • You have peace of mind and certainty knowing without question whether the injectors are good or not.


Link to: Returning engine power through fuel injector cleaning service.



  • The “time” factor, where the injectors have to be removed from the car and taken in or sent to an injector shop.  This adds a few days to the diagnosis and repair process.  We feel the extra time is well worth it for the peace of mind.


Save money by cleaning and flow testing your injectors!

  • New injectors can cost from $70 to $250 each.  Our Fuel injector cleaning and flow testing service costs only $17 for each injector.
  • Most customers experience a 10 to 15% improvement in gas mileage after getting their injectors ultrasonically cleaned and flow tested.  Depending on how much you drive, that is like getting 5 days of free driving per month!!

Why pay for new or re-manufactured (used) fuel injectors when you can service your injector(s) to “like new” for a fraction of the cost?