Throttle Body Injection (TBI)

Throttle Body Injection or TBI, uses one or two injectors mounted directly in the throttle body which spray fuel into the intake manifold. With this system, fuel pressure is created by an electric fuel pump typically mounted in or near the fuel tank with the pressure being controlled by a regulator mounted on the throttle body. An engine computer fires the injectors, which occurs in a series of short rapid bursts rather than a continuous stream. This produces a buzzing noise from the injectors when the engine is running.

TBI can be limiting as a fuel injection method because the same fuel distribution issues that affect carburetors also affect TBI systems. However, TBI systems have much better cold start performance than carburetors because they provide better atomization and do not have a mechanical choke. TBI systems also makes it easier for the electronic engine control system to regulate the fuel mixture than a carburetor. Throttle Body Injection systems were only used briefly during the 1980′s as vehicle manufacturers moved from carburetors to fuel injection to meet U.S. emission regulations. By the late 1980′s, most TBI systems were replaced with Multiport Injection (MPI) fuel injection systems.

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When the auto and motorcycle industry moved to Electronic Fuel Injection (EFI), the need for professional injector cleaning as an affordable cost became an attractive alternative to expensive injector replacement. ProFlow can help restore lost power and performance to your engine with our Ultrasonic Fuel Injector Cleaning Service.

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