Are there any drawbacks to a return style fuel system?
This system does have a few drawbacks however, beyond the potential negative environmental effects. Return-style systems require fuel pumps to work all the time —it never shuts off as long as the engine’s running, which can shorten the life of the pump.
Do you need to retrofit a fuel return line?
It’s an easy question to answer on vehicles that already have a fuel return line…or at least the routing room for one. Retrofitting a returnless system can get expensive, requiring a new pump, regulator, and plumbing. But that’s not to say your vehicle’s returnless system isn’t pretty darn good.
How does a returnless fuel system work in a car?
A returnless fuel system uses an in-tank pump and regulator. A single fuel line exits the tank and travels to the engine. Pressure is controlled by a computer, which monitors a series of engine sensors to determine how much fuel to deliver. To regulate the fuel pressure, the ECU simply adjusts the pump speed or fuel injector rate.
What to watch out for on a returnless EFI system?
Something else to watch out for on returnless EFI systems is contaminants in the fuel rail on the engine. The rail is a dead end as far as fuel circulation is concerned. Fuel flows one-way into the rail and does not return to the tank, so any junk that gets past the fuel filter will end up in the rail or injectors.
What are the benefits of a return style fuel system?
There are some key benefits to a return-style setup. Vapor lock is mitigated because the constant cycle of fuel back into the tank cools the gasoline. Engine tuning is easier because the fuel temperatures in a return-style system are typically more consistent.
It’s an easy question to answer on vehicles that already have a fuel return line…or at least the routing room for one. Retrofitting a returnless system can get expensive, requiring a new pump, regulator, and plumbing. But that’s not to say your vehicle’s returnless system isn’t pretty darn good.
How does a return style fuel injector system work?
Return style systems hold a big advantage in that with a vacuum/boost referenced fuel pressure regulator, the system can maintain a CONSTANT effective fuel pressure, which can extend the range of fuel injectors and help them function at lower fuel demands as well.
Why do you need bypass regulator in return style fuel system?
Consequently, by decreasing the line pressure between the fuel pump and the regulator, a return-style fuel system actually increases fuel flow. Adding a bypass regulator goes a long way in combating vapor lock, but the fuel filter shouldn’t be overlooked, either.