The Ford F150 Obd2 Code 32 indicates an issue with the Evaporative Emission (EVAP) system. However, this article focuses on the Thick Film Ignition (TFI) system diagnostics and troubleshooting, which can be indirectly related to various performance issues, sometimes mistaken for EVAP problems. This guide provides a comprehensive overview of the TFI-IV system in a Ford F150 and outlines troubleshooting steps for common issues.
Understanding the Ford F150 TFI-IV Ignition System
The Thick Film Integrated (TFI-IV) ignition system is a crucial component in Ford F150s, responsible for generating the spark that ignites the air-fuel mixture in the engine cylinders. This system utilizes a camshaft-driven distributor without centrifugal or vacuum advance. A Hall effect stator assembly is integrated into the distributor’s diecast base. The TFI-IV module, mounted on this base, uses a 6-pin connector and an E-Core ignition coil, named for the shape of its core laminations.
The TFI-IV module powers the Profile Ignition Pick-up (PIP) sensor, which relays crankshaft position data to the module. This information is then sent to the Electronic Engine Control (EEC-IV) module. The EEC-IV module determines the optimal spark timing and signals the TFI-IV module to deactivate the coil, generating the spark.
The distributor operation relies on the Hall effect stator assembly. This assembly triggers the on/off switching of the ignition coil based on signals from the EEC-IV and TFI-IV modules. The vane switch, a sealed unit, contains a Hall sensor and a permanent magnet. A rotating vane cup, made of ferrous metal, activates the Hall effect switch. The magnetic flux field changes as the vane passes through the opening, generating a voltage signal. This signal informs the EEC-IV system about crankshaft position, enabling it to calculate the required spark advance. Voltage distribution happens through a standard rotor, cap, and ignition wires.
General Testing Procedures for the TFI-IV System
Spark Plug Wire Resistance
Before disconnecting or reconnecting high-tension wires, apply silicone grease (Ford silicone grease D7AZ-19A331-A, Dow Corning #111, or General Electric G-627) to the boot using a clean screwdriver blade. Measure the resistance of each wire; it should not exceed 5,000 ohms per foot. Always measure from end to end without piercing the wire.
Adjustments
The air gap within the distributor and the amplifier module are not adjustable. Faulty components require replacement. Connecting components outside the vehicle can lead to damage.
Troubleshooting the TFI-IV System
Seal any pierced wires with silicone sealer after testing.
Wiring Harness
Disconnect the TFI module’s wiring harness connector by pushing the tabs. Check for damage, dirt, or corrosion. With the ignition in the RUN position, use a voltmeter to measure voltage at the TFI module connector terminals (No.1 and No.2). Then, switch the ignition to START and check the voltage at terminal No.3. All readings should be at least 90% of the battery voltage. Low readings indicate potential issues with the wiring, connectors, or ignition switch. A low reading at only terminal No.1 suggests further testing of the ignition coil primary voltage.
Stator Assembly and Module
Remove the distributor and TFI module. Inspect for damage. Measure the stator assembly’s resistance. A reading between 800-975 ohms indicates a faulty TFI module. Readings outside this range point to a faulty stator. Replace the necessary component.
Primary Circuit Continuity
Repeat the Wiring Harness test for terminal No.1 with the ignition in the RUN position. If the voltage is below 90% of the battery voltage, proceed with the coil primary voltage test.
Conclusion
While OBD2 code 32 directly relates to the EVAP system, a malfunctioning TFI system can contribute to poor engine performance. This guide offers valuable insights into the TFI-IV system and its troubleshooting process. By following these steps, you can identify and resolve issues within the TFI-IV system, ensuring optimal performance for your Ford F150. Remember to consult a qualified mechanic for complex issues.
