Throttle Position Sensor

Replace the throttle position sensor (TPS) on the 6.0L V12 engine to restore proper throttle position feedback to the engine control unit.

Warnings

Tools required

Parts

• Throttle position sensor × 1 — Use OEM specification - Aston Martin/Ford part
• TPS mounting screws (if corroded) × 2 — Use OEM specification

Preparation

1. Ensure engine is completely cold to the touch
2. Park vehicle on level surface and engage parking brake
3. Open hood and secure with prop rod
4. Disconnect negative battery terminal to prevent fault codes and allow ECU reset
5. Remove engine cover by lifting upward - it is secured by rubber grommets on posts
6. Photograph throttle body wiring harness routing for reference during reassembly

Procedure

1. 1

   Access throttle body area
   Locate the throttle body assembly on the intake plenum. On the 6.0L V12, the engine uses a single electronic drive-by-wire throttle body mounted at the main air intake inlet to the intake manifold. Verify the exact throttle body location against Aston Martin service documentation before proceeding. Identify the single throttle body containing the TPS being serviced; access may require removing acoustic covers over the intake. Remove any acoustic insulation or heat shielding that obstructs access to the throttle body using Torx fasteners as equipped. The TPS is integrated into the electronic throttle body actuator. Note that this is a drive-by-wire system with no mechanical throttle cable. Note: On the 6.0L V12, the electronic drive-by-wire throttle body is located at the main air intake inlet to the intake manifold. Verify exact location against Aston Martin service documentation before proceeding. Note: On the 6.0L V12, verify throttle body configuration before proceeding — this engine typically uses dual throttle bodies (one per cylinder bank) rather than a single central unit. Confirm the location and number of throttle position sensors with model-specific documentation before continuing.
2. 2

   Disconnect air intake ducting
   Loosen the hose clamp securing the air intake duct to the throttle body inlet using a flat-blade screwdriver or the appropriate hex socket for the fitted clamp. Carefully pull the intake duct away from the throttle body. If the duct is stiff, gently twist while pulling to break the seal. Set the duct aside without placing stress on any attached sensors or hoses.
3. 3

   Locate and identify TPS connector
   Identify the throttle body actuator electrical connector. On this electronic (drive-by-wire) throttle body the connector commonly has 5 or 6 pins (combining the throttle motor and integrated position sensor circuits) with a locking tab. Verify the exact connector configuration for the fitted unit. Note the orientation and routing of the wiring harness. The connector may have a secondary lock or safety clip that must be released before the primary connector lock. Note: It is typically a multi-pin connector (often 6-pin on electronic drive-by-wire throttle bodies, which integrate dual position sensors and the throttle actuator motor) with a locking tab.
4. 4

   Disconnect TPS electrical connector
   Press down on the connector locking tab while pulling the connector straight away from the TPS. If equipped with a secondary safety clip (a small sliding lock), slide it toward the wire bundle first, then release the primary lock. Do not pull on the wires themselves. If the connector is resistant due to corrosion or environmental sealing, gently work it side to side while applying outward pressure.
5. 5

   Remove TPS mounting screws
   If the sensor is confirmed to be a discrete, separately serviceable component, locate its mounting screws on the throttle body (verify exact count against Aston Martin service documentation; on integrated units the complete throttle body must be replaced instead). These may be Torx screws; verify the exact drive type and size against the fitted fasteners and Aston Martin service documentation before removal. Using the appropriate Torx driver, carefully remove both screws. Support the sensor with your other hand as you remove the second screw to prevent it from falling into the engine bay. Note the screw length and any washers or seals present. Note: Verify the exact fastener drive type and size against Aston Martin service documentation before removal; no verified size is available for this application.
6. 6

   Remove old TPS from throttle body
   Verify whether the position sensor is a separately serviceable component or integrated into the electronic throttle body assembly. On many 2009 DB9 applications the sensor is not separately replaceable and the complete throttle body must be replaced. If a discrete sensor is confirmed serviceable, gently pull it straight away from the throttle body, using a slight wiggling motion if needed, without rotating or twisting the throttle plate. Inspect the mounting surface on the throttle body for debris, corrosion, or damage. If an O-ring or gasket is present on the old sensor or throttle body, remove it completely. Note: Verify whether the TPS is a separately serviceable component or integrated into the electronic throttle body. If serviceable, gently pull the TPS straight away from the throttle body; the sensor may require a slight wiggling motion to disengage. Do not rotate or twist the throttle plate during removal. If the sensor is integral to the throttle body, the complete throttle body assembly must be replaced. Note: If the sensor is a separate bolt-on unit, its shaft may engage the throttle plate shaft and require a slight wiggling motion to disengage; however, verify whether the position sensor is integrated into the electronic throttle body as a non-serviceable assembly, which would require replacing the entire throttle body instead.
7. 7

   Inspect throttle body shaft and clean mounting surface
   Examine the throttle plate shaft where the TPS engages. Look for wear, scoring, or debris. The shaft should be clean and free of corrosion. Use contact cleaner on a lint-free cloth to clean the TPS mounting surface on the throttle body. Ensure no debris will interfere with the new sensor's seal or shaft engagement. Do not spray cleaner directly into the throttle body bore.
8. 8

   Prepare new TPS for installation
   Remove the new TPS from packaging and verify it matches the old unit in connector type, mounting hole pattern, and shaft engagement design. If the new sensor includes a gasket or O-ring, ensure it is properly seated in the sensor body groove. Check that the sensor shaft rotates freely and is not binding.
9. 9

   Install new TPS onto throttle body
   Align the TPS shaft with the throttle plate shaft on the throttle body. The sensor will only fit in one orientation due to shaft key or flat design. Gently slide the sensor onto the throttle body, ensuring the shaft engages properly. The sensor should seat flush against the throttle body mounting surface. Do not force - if resistance is met, remove and verify shaft alignment.
10. 10

    Install and torque TPS mounting screws
    Insert both TPS mounting screws by hand, starting them evenly to avoid cross-threading. Once both screws are hand-tight and the sensor is properly seated, torque the screws evenly to the manufacturer-specified value using a torque wrench (confirm the exact torque spec in Aston Martin service documentation — no verified value is provided here). Do not overtighten as this can crack the sensor housing or strip the throttle body threads. Note: Once both screws are hand-tight and the sensor is properly seated, torque the screws in a cross pattern to the manufacturer-specified value (typically low, in the 2-4 Nm range for small sensor fasteners — verify against model-specific documentation) using a torque wrench.
    Torque spec

    TPS Screws3 Nm (2 lb-ft)
11. 11

    Reconnect TPS electrical connector
    Align the TPS electrical connector with the sensor pins, ensuring correct orientation (the connector is keyed and will only fit one way). Push the connector firmly onto the sensor until you hear or feel the locking tab click into place. If equipped with a secondary safety lock, slide it back into the locked position. Gently tug on the connector to verify it is secure.
12. 12

    Reinstall air intake ducting
    Position the air intake duct onto the throttle body inlet, ensuring proper alignment and full seating. Tighten the hose clamp securely, but do not overtighten to the point of deforming the duct or damaging the throttle body inlet. Verify all attached sensors and hoses are properly routed and not kinked or stressed.
13. 13

    Reinstall engine covers and reconnect battery
    Replace any heat shielding or acoustic insulation removed during disassembly, securing with original fasteners. Position the engine cover onto its mounting posts and press down firmly until all grommets are fully seated. Reconnect the negative battery terminal and tighten securely.

Reassembly

1. Ensure all electrical connectors are fully seated and locked with audible clicks
2. Verify intake ducting clamp is secure and duct is not collapsed or kinked
3. Confirm engine cover is properly seated on all mounting posts
4. Double-check that no tools or parts were left in engine bay

Verification

• Turn ignition to ON position (do not start engine) and verify no check engine light or throttle-related warning messages appear on instrument cluster
• With ignition ON, have an assistant slowly press accelerator pedal while you observe throttle plate movement - it should open smoothly without binding or hesitation
• Start engine and allow it to idle - idle should be stable without hunting or surging after brief ECU adaptation period
• Perform a test drive including gentle acceleration, part-throttle cruising, and deceleration - throttle response should be smooth and linear without hesitation or dead spots
• If equipped with diagnostic scan tool, verify TPS voltage readings change smoothly from approximately 0.5V at closed throttle to 4.5V at wide-open throttle
• Monitor for any stored or pending throttle position related fault codes after test drive

Related trouble codes on this vehicle

Codes that commonly send this job to the bay — tap one for symptoms, causes, and diagnostic steps.

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