Parts for your 2004 Honda Civic-Throttle position sensors

2004 Honda Civic throttle position sensor: what it does and how to look after it

Based on the Honda Factory Service Manual for the 2001–2005 Civic range (Fuel & Emissions and PCM Inputs sections), Honda’s electronic parts catalogue for those model years, and mainstream service information databases (e.g., Mitchell 1 and ALLDATA), the 2004 Honda Civic is fitted with a throttle position sensor (TPS) on the throttle body. The manuals include TPS testing procedures and the PCM relies on this signal for fuelling and ignition, with OBD‑II diagnostics listing relevant fault codes such as P0120, P0121, P0122, P0123 and P0124. That confirms the TPS is relevant and used on the 2004 Civic across D‑series engines, and on K‑series variants (Si/Type R) where the TPS is integrated with the throttle body assembly in the OE catalogue.

On a 2004 Civic, the TPS tracks the angle of the throttle plate and sends a changing voltage to the powertrain control module. That lets the PCM fine‑tune fuel delivery, ignition timing and, on automatic models, shift behaviour. Paired with the MAP sensor and idle air control system, it helps the engine feel crisp off the line, smooth at cruise and responsive when overtaking.

The TPS isn’t a scheduled replacement item, but it deserves attention during regular servicing, especially on higher‑kilometre cars. A quick scan‑tool check of TPS percentage and a visual inspection of the connector and wiring go a long way. If drivability goes a bit pear‑shaped, common clues include:

• Hesitation or flat spots on light throttle, erratic idle or stalling
• Poor fuel economy and sooty plugs
• Harsh or late shifts on autos
• Check Engine Light with TPS‑related DTCs (P0120–P0124)

For D‑series throttle bodies, the TPS is a separate sensor fixed with tamper‑resistant screws. Replacement is straightforward for a competent technician: transfer the sensor, align it so closed‑throttle voltage sits around 0.45–0.55 V (check the Honda spec), then clear codes and carry out an idle/PCM relearn. Avoid spraying cleaners into the sensor, clean the throttle bore only. On K‑series Civic variants of this era, Honda often supplies the TPS with the throttle body as one unit, many workshops either replace the assembly or use a high‑quality sensor and calibrate it carefully.

Handy servicing tips:

• Back‑probe the TPS and sweep the throttle, the voltage should rise smoothly to about 4.5 V without dropouts.
• Inspect earths and the engine harness near the throttle body for heat or rub damage.
• After any throttle body/TPS work, perform the specified idle learn so the PCM can re‑optimise.

Popular questions: 2004 Honda Civic throttle position sensor

Does a 2004 Honda Civic have a TPS or is it drive‑by‑wire?
Yes, it has a TPS. The 2004 Civic uses a cable‑actuated throttle body with a throttle position sensor that feeds the PCM. Electronic throttle (drive‑by‑wire) came later on Civics in the following generation.

What are the symptoms of a failing TPS on a 2004 Civic?
Owners often notice hesitation on light throttle, surging or hunting idle, poor fuel use, harsh shifts on autos and a Check Engine Light with codes like P0121–P0123. A scan tool will show erratic TPS percentage or a dead spot when the pedal is moved slowly.

Can the TPS be replaced on its own, or does the whole throttle body need changing?
On most D‑series 2004 Civics, the TPS can be replaced on its own and calibrated. On some K‑series variants, Honda lists the TPS with the throttle body assembly, so workshops may replace the whole unit or fit a quality sensor and align it to spec. Always confirm against the vehicle’s VIN/engine code.