So, the function of fuel systems, is to store and deliver fuel, to the engine as needed.

Furthermore, as the fuel is delivered, it must also be, atomized and have the correct, spray pattern.

In addition, the fuel needs to be, under a certain pressure and volume, for proper combustion to take place.

Consequently, fuel systems can be, one of two different types. Either, the return type or return less type. But, the big difference is, how they are actually regulated.

Return type system

So, a return type system, has a fuel pressure regulator, that varies the fuel pressure. But, is based on the amount of vacuum, from the intake system. This is so, the amount of fuel pressure and flow reaching the injectors, remains consistently the same.

Return less system

Whereas a return less type system, uses the powertrain control module (PCM) to regulate fuel delivery. As a result, when the fuel pressure and flow starts to drop, due to increase of engine speed or load. Consequently, the (PCM) compensates by, increasing injector duration and/or operating speed, of the fuel pump.

Signs of failing fuel systems include:

  • Difficult Engine Starting.
  • Slow or Hesitation at Acceleration.
  • Stalling While Driving.
  • Intermittent Power Loss.
  • Check Engine Light or Service Engine Soon Light Illuminated.
  • Engine Idling Rough.
  • Excessive Engine Smoke.
  • Noticeable Fuel Odors.
  • Decreased Fuel Economy.

Choose Your Fuel Systems Help Topic Below

Electronic Fuel Injectors – Are Used To Convert Fuel Into A Fine Spray

Fuel Pressure Regulator – Controls The Exact Amount Of Fuel Pressure

Fuel Pump Relays – Allows Current Through To The Fuel Pump

Automotive Fuel Pumps – Deliver Fuel From The Fuel Tank To The Engine

Gasoline Direct Injection (GDI) – New Technology Causes New Problems

Fuel Leak – If You Smell Fuel This Could Be A Sign Of A Fuel Leak

Fuel System Related Problems – Not Always Easy To Solve

Poor Fuel Economy – Little Tricks That Will Help In Boosting Your Mileage

Fuel Pump Related No Start Problems – What Should You Check

Excessive Fuel Consumption – Common Causes And Cures

Fuel Getting Into Engine Oil – Causing Premature Wear Of Engine Parts

Fuel Wash – How To Eliminate This Potentially Serious Problem

Reducing Fuel Consumption – Keep More Money In Your Pocket

Hard Starting Engine – Cold, Hot, Both Or Just After Refueling

Engine Fuel System Testing – Proper Testing With Solutions

Gas Getting Into Oil – What Can Cause This To Happen ?

Oxygen Sensors (O2) – They Monitor The Levels Of Fuel Mixture

Automatic Shutdown (ASD) Relay – Function – Failure – Testing

Fuel Pump Issues – Excessive Heat – Contamination From Dirt and Rust

Loose Gas Cap – Evaporative Emission Control System (EVAP) Self Test

Thank You !