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Frequently features grey plastic connectors with high-density pin layouts.
The Toyota 4S-FE engine is a legend of reliability. Found in iconic 1990s vehicles such as the Toyota Corona (T170/T190), Celica (T200), Carina E, and Caldina, this 1.8-liter, 16-valve, twin-cam (DOHC) engine is known for its smooth power delivery and mechanical simplicity. 4s-fe ecu pinout
This is where people smoke harnesses.
12V power from the EFI relay when the ignition is ON. Don’t buy a scanner
Oxygen Sensor input. Delivers a fluctuating 0-1V signal to help the ECU adjust stoichiometric fuel ratios during closed-loop operation. Communications and Dash Interfaces
| Pin | Type | Signal Name | Function | |:---:|:---:|:---:|:---| | 3 | Input | | Engine Coolant Temperature Signal | | 5 | Input | THA | Intake Air Temperature Signal | | 4 | Input | PIM | Intake Manifold Pressure Signal (for some markets) | | 7-8 | Input | VTA / VCC | Throttle Position Sensor Signal | | 9 | Input | NE | Crankshaft RPM Signal (from distributor) | | 21 | Input | NE (Alt.) | RPM Signal (alternate pin) | | 10 | Input | OX | Oxygen Sensor (Lambda) Signal | | 23 | Input | KNK | Knock Sensor Signal | | 16 | — | E2 | Sensor Ground (return for sensors) | | 24 | Ground | E1 | Computer Ground (main ground) | The Toyota 4S-FE engine is a legend of reliability
The igniter sends a signal back to the ECU on this pin to confirm the coil fired. If the ECU doesn't see IGF, it will cut fuel for safety.
These inputs allow the ECU to calculate load, fueling, and timing advance. Function Description Signal Range Intake Manifold Pressure (MAP Sensor) 0.5V - 4.5V THW Engine Coolant Temperature (ECT) 0.5V (Hot) - 4.5V (Cold) THA Intake Air Temperature (IAT) 0.5V (Hot) - 4.5V (Cold) VTA Throttle Position Sensor (TPS) signal 0.5V (Idle) - 4.5V (WOT) IDL Idle Switch contact point inside TPS 0V (Idle) / 12V (Off-Idle) OX Oxygen Sensor voltage signal 0.1V (Lean) - 0.9V (Rich) KNK Knock Sensor signal AC Frequency Actuators and Auxiliary Outputs
Provide top dead center (TDC) reference points for cylinder identification.
To read codes: jump to E1 with ignition ON, count CEL flashes.