Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Fuel Injection System - Multi-Point: Description
The Chrysler Multi-Point Electronic Fuel Injection system is an electronically controlled system which combines electronic fuel injection and electronic spark advance system with a turbocharged intake system. The main sub-systems consist of: Air Induction, Fuel delivery, Fuel Control, Emission Control, Logic Module, Power Module and Data Sensors.
The Air Induction system includes air cleaner, throttle body, throttle position sensor (TPS), automatic idle speed (AIS) motor and turbocharger assembly.
The Fuel Delivery system provides fuel from the fuel pump to the fuel control system. It also returns excess fuel to the fuel tank. the system is composed of an in-tank electric fuel pump, fuel filter, check valves and return line. Power is provided to operate the fuel pump through an automatic shut-down (ASD) relay from the power module.
The Fuel Control system handles the actual delivery of fuel into the engine. The fuel pressure regulator maintains a constant fuel pressure of 53 psi (3.7 kg/cm2 ). In addition to the regulator, the system consists of the fuel rail and 4 fuel injectors.
Emission systems controls, although directly operated by the logic module, are not unique to the multi-point EFI engine. These controls include EGR, aspirated air system, evaporative emission control and crankcase ventilation.
The logic module is a digital microprocessor computer. This module is the "brain" of the system. All calculations and control functions are performed by the logic module. The power module is a small computer that contains necessary circuitry to power the ignition oil and fuel injectors. This module supplies most of the operating current for the system.
Data sensors consist of various sensors and switches which provide the logic module with engine operating information. The computer analyzes this information and corrects air/fuel ratio, ignition timing, and emission control as needed to maintain efficient ngine operation.
NO RELATED
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.