Parts for your 2009 Lexus Is-Map sensor

2009 Lexus IS MAP sensor — what’s fitted and how to look after it

Yes, the 2009 Lexus IS range uses a MAP (Manifold Absolute Pressure) sensor. This applies across the main engines of the era — 4GR‑FSE (IS 250), 2GR‑FSE (IS 350) and 2UR‑GSE (IS F). This isn’t guesswork: the Lexus/Toyota repair manual procedures for the IS platform include MAP sensor diagnostics (e.g., DTCs P0106–P0108), and the Toyota/Lexus Electronic Parts Catalogue lists a “Sensor, Manifold Absolute Pressure” for these engines. Denso service literature for Toyota V6 and V8 applications of the period also describes the MAP sensor’s role alongside the MAF in load calculation and EGR/VVT control.

The MAP sensor measures absolute pressure inside the intake manifold. The ECU uses that signal to understand how much air is actually making it into the engine under real conditions — altitude, throttle position, cam timing, and all. Even though the IS runs a MAF sensor as the primary load input, the MAP backs it up, improves transient response, and helps with fuelling, ignition timing and EGR checks. That’s why a dicky MAP can make an otherwise healthy Lexus feel flat or hunt at idle.

Typical clues a MAP sensor needs attention include rough idle, hesitant take-off, sootier exhaust, increased fuel use, or the check engine light with codes like P0106, P0107 or P0108. On the 2009 IS it’s mounted on the intake manifold near the throttle body, sealed with an O‑ring.

As part of routine servicing, it’s worth a quick inspection:

• Check the connector and wiring for corrosion, oil wicking or broken locks.
• If there’s oily vapour build-up in the manifold, remove the sensor and gently clean the tip and port with a sensor‑safe electronics cleaner. Don’t poke the port with wire or blast it with compressed air.
• If the O‑ring looks flattened or cracked, replace it to avoid vacuum leaks.

Replacement is straightforward: key off, pop the connector, undo the small bolts, swap the sensor and O‑ring, then snug the bolts (light torque — these are small fasteners, typically around 3–5 N·m). Clear any stored codes, then let the engine idle until warm and take a short drive so the ECU trims settle. No special programming is normally required.

A healthy MAP sensor helps the 2009 IS keep its smooth throttle feel, tidy fuel economy and clean emissions — exactly what owners expect from a Lexus.

Popular questions about the 2009 Lexus IS MAP sensor

Where is the MAP sensor on a 2009 Lexus IS?
It’s bolted to the intake manifold close to the throttle body. On IS 250/IS 350 it’s easy to see with the engine cover off — a small rectangular sensor with a two‑bolt flange and an electrical connector. The IS F location is similar, just tighter for access due to the intake layout.

What symptoms point to a bad MAP sensor?
Common signs include rough or surging idle, lazy throttle response, higher fuel use, and a check engine light. Scan tools often show codes P0106, P0107 or P0108. Live data that doesn’t change with throttle input, or manifold pressure readings that look unrealistic at idle or cruise, also point to a failing sensor.

Do I need to program the ECU after replacing the MAP sensor?
No special coding is usually needed. Clear fault codes, start the car, let it idle until warm, and drive normally so fuel trims relearn. If idle is unstable after replacement, check the O‑ring seal and connector, then recheck for vacuum leaks.