🚨 Diagnostic Profile
Vehicle/Equipment Make: ACURA
Technical Description: Throttle Position Insufficient
This diagnostic trouble code indicates that the Engine Control Module (ECM) has detected a Throttle Position (TP) sensor voltage signal that is lower than the expected minimum calibrated value. This typically points to an issue within the Electronic Throttle Body (ETB) assembly, its wiring harness, or the ECM’s ability to correctly interpret the throttle plate’s actual position during idle or acceleration.
🚨 Repair Difficulty Tier
Rating: [Intermediate]
This repair is generally classified as Intermediate. While the physical replacement of the throttle body assembly involves basic hand tools, accurately diagnosing this specific Acura fault code requires a bi-directional scan tool capable of reading live sensor data (PID) and monitoring voltage correlation between TP Sensor 1 and TP Sensor 2. Additionally, most Acura/Honda platforms require a specific ‘Electronic Throttle Body Relearn/Reset’ procedure using an OEM-level scanner (such as a Honda Diagnostic System – HDS) after any component replacement or ECM disconnection to properly recalibrate the idle stop position.
🛠️ Resolution Steps
Step 1: Preliminary Inspection
Begin by visually inspecting the electrical connector attached to the throttle body assembly. Check for corrosion, bent pins, or a partially disengaged locking tab. Trace the wiring harness from the throttle body back to the ECM, checking for chafing, rodent damage, or pinch points near the intake manifold. Additionally, inspect the throttle body bore for excessive carbon buildup, as heavy carbon deposits can mechanically restrict the throttle plate from returning to its true ‘closed’ calibrated position.
Step 2: Diagnostic Verification
Connect an OEM-level scan tool (HDS) or a high-quality aftermarket scanner capable of bi-directional Honda/Acura control. Access the Throttle Position Sensor PIDs and monitor live data for both TP Sensor 1 and TP Sensor 2 while manually moving the throttle plate (with the engine off and key on). The voltage should rise and fall smoothly and simultaneously on both sensors without any dead spots or sudden drops. If the scanner reports a voltage reading of near 0V or below the standard 0.5V baseline at idle, this confirms an internal sensor fault or wiring open circuit. Use a multimeter to verify a steady 5V reference voltage and confirm proper ground continuity at the throttle body connector if the scan tool data appears erratic.
Step 3: Resolution & Reset Process
If the sensor signal is confirmed faulty or if there is significant carbon buildup preventing proper plate closure, replace the entire Electronic Throttle Body (ETB) assembly, as the TP sensor is integrated and non-serviceable separately on most Acura models. After installing the new component and reconnecting the harness, you must perform the Idle Learn/Throttle Body reset procedure via the HDS scan tool. Failure to perform this reset will result in a rough idle or persistent stored codes even with a new, functioning part installed. Clear all DTCs and perform a test drive to confirm the code does not return under various load conditions.
📦 Parts, Labor, and Budget Estimates
Required Components/Software: Electronic Throttle Body Assembly, OEM-level Scan Tool (HDS) or advanced bi-directional scanner for reset capability, Electrical contact cleaner.
Average Component Price: $250 – $450 (OEM part); Programming/Reset typically included in standard diagnostic labor if using a capable scan tool.
Estimated Labor Hours: 1.5 – 2.0 hours (Includes diagnostic time, physical replacement, and required ECM relearn/reset procedure).