Parts for your 2008 Honda Accord-Throttle position sensors

2008 Honda Accord throttle-position-sensor: what it does and how to look after it

For the 2008 Honda Accord, a throttle position sensor (TPS) is absolutely relevant and used. Honda’s own technical literature — the Accord 2008–2012 Service Manual (PGM‑FI Electronic Throttle Control System) and the Honda Electronic Parts Catalogue — shows the throttle body houses dual throttle position sensors (often called TP Sensor A and B). These are integrated with the drive‑by‑wire throttle body and aren’t sold as a separate, bolt‑on sensor. Trade databases such as Alldata and Mitchell likewise list TPS signals as part of the electronic throttle system, confirming it’s built in, not a standalone part.

On this Accord (both four‑cylinder and V6), the TPS tells the engine computer exactly how far the throttle plate is open. That info is blended with inputs from the accelerator pedal position sensor, airflow and other data to manage fuel delivery, ignition timing and idle speed. The goal: smooth response, good economy and lower emissions.

There’s no routine replacement interval for the TPS on a 2008 Accord because it’s part of the throttle body. During regular servicing, the smart play is preventative care:

• Inspect the intake duct and throttle body for carbon build‑up, clean the throttle bore carefully if deposits are visible.
• Avoid soaking the throttle body with harsh cleaner, don’t force the throttle plate by hand on a drive‑by‑wire unit.
• If drivability issues pop up (hunting idle, surging, flat spots, limp mode) scan for DTCs such as P0121–P0123 or related TP/ETC faults, and view live data for smooth, matching TP Sensor A/B tracks.

If the TPS circuit is faulty, the fix is to replace the complete throttle body assembly and fit a new gasket. After any throttle body work or heavy cleaning, perform the Honda idle learn/electronic throttle relearn so the ECU can recalibrate. A capable scan tool makes this faster and helps confirm the repair. It’s also worth checking the accelerator pedal position sensor data, as the ECU compares both sides (pedal and throttle) for safety.

With sensible cleaning, good air filtration and proper relearn procedures after service, the 2008 Accord’s throttle position sensing stays reliable for many kilometres.

Popular questions

Does a 2008 Honda Accord have a separate throttle position sensor?
Yes and no. It definitely has throttle position sensing, but it’s built into the electronic throttle body as dual sensors. Honda doesn’t supply the TPS separately, the repair part is the throttle body assembly.

Can the TPS be replaced on its own?
Not on this model. If testing confirms a TP sensor fault, the correct repair is to replace the entire throttle body, then carry out an idle/throttle relearn. That’s how Honda specifies it in the service information and parts catalogue.

What are common symptoms of a failing TPS on a 2008 Accord?
Drivers might notice a wandering idle, hesitation off the line, sudden surging, poor fuel economy, or the Check Engine light. Scan tools may show codes like P0121–P0123 or mismatched TP Sensor A/B readings. Always check the accelerator pedal sensor data too, as the system cross‑checks both.