Does the Infiniti FX35 need to be matched after cleaning the throttle body?
3 Answers
Whether the Infiniti FX35 needs to be matched after cleaning the throttle body depends on the type of throttle body. Throttle bodies are divided into cable throttle bodies and electronic throttle bodies. All cable throttle bodies do not require matching, while electronic throttle bodies do. The Infiniti FX35 is a sports-style SUV equipped with a VQ35HR 3.5L V6 engine, delivering a maximum power of 244 kW. The FX50, equipped with a 5.0L V8 naturally aspirated engine, offers a maximum power of 317 kW and a maximum torque of 500 Nm per meter. The main configurations of the Infiniti FX35 include dual-zone automatic climate control, an onboard navigation system, a rear-seat DVD entertainment system, heated front seats, and a rearview camera system.
Last time I cleaned the throttle body of my FX35 myself, and the idle speed became extremely unstable, with the tachometer jumping up and down. After checking some materials, I learned that electronic throttle bodies must be recalibrated after cleaning because the ECU's recorded opening angle differs when it's dirty versus after cleaning. I connected a specialized diagnostic tool to the OBD port, entered the engine system, and selected the throttle calibration option, then waited for the process to complete. If you skip this step, at best, you’ll have unstable idle and poor fuel efficiency, and at worst, the engine might stall or leave you stranded. For older Infiniti models like this, it’s strongly recommended to perform the calibration—don’t trust the online "disconnect the battery" reset tricks; they simply don’t work. I later went to a repair shop and spent 50 bucks to get it done, and now cold starts are rock steady.
As a seasoned car enthusiast with over a decade of experience, I'm extremely familiar with throttle body adaptation. The Infiniti FX35 absolutely requires adaptation after cleaning the throttle body, especially older models which are more prone to issues. Last week when helping a friend with this car, the RPM fluctuated wildly and even the AC vibrated before adaptation. The reason is simple: the ECU still controls air intake based on the old throttle opening values while the cleaned throttle body has different actual openings. Using equipment like the Launch X431, connect to the diagnostic port, select throttle adaptation in special functions, and it's done in three minutes. Remember to let coolant temperature reach 90°C before adaptation, turn off all electrical loads, and after adaptation take it for a short drive to let the ECU complete self-learning.
