Technical Knowledge Base




Technical PG 2
Let's Get Technical!
cont from pg 1- Emission Control Systems
the following is a graph showing the changes in the modern engine compared to the pre-computer days:
Carbureted Engines
Distributor Cap w/module & pick-up

Feedback Carburetor controlled by various sensors

Timing control by spark control system or vacuum advance

Some exhaust systems use cat convertors & Oxygen sensors (usually one)but not very accurate

Fuel Injected Engines
Distributorless Ignition utilizing cam & crank sensors

Fuel is delivered via high pressure system utilizing electric fuel pump, one or more injectors also controlled by various sensors

Timing controlled by computer- not adjustable- utilized input from various sensors to control advance, some have variable cam timing

Exhaust systems very efficient using Convertors with 2 or more O2 sensors, pre & post convertor to acurately control short & long term fuel trims ratios