Parts for your 2018 Toyota Wish-Map sensor

2018 Toyota Wish MAP sensor: what it does and when to service it

Yes, the 2018 Toyota Wish (late ZGE2# series with 2ZR-FAE or 3ZR-FAE engines) uses a manifold absolute pressure (MAP) sensor. Toyota’s Electronic Parts Catalogue for ZGE20/25 models lists a “Sensor, Manifold Absolute Pressure (PIM)” for these engines, and the Toyota workshop manuals describe the MAP signal’s role in load calculation, EGR control and altitude correction alongside the MAF sensor. Denso’s application data likewise shows MAP sensor fitment for ZR-family engines used in Wish. So it’s absolutely relevant on this vehicle.

The MAP sensor measures pressure in the intake manifold so the ECU can work out how much air is effectively making it into the cylinders. That info is blended with MAF, throttle, RPM and temperature data to get fuelling and ignition spot on, keep idle steady, and keep emissions in check. It also helps the Wish adjust for altitude on those weekend drives up into the ranges.

It’s a robust, solid-state bit of kit and not a routine replacement item, but it does benefit from inspection during servicing. Under the bonnet, it’s mounted to the intake manifold with an O-ring seal and a single electrical plug. During air filter changes (every 30–40,000 kilometres is a fair guide), it’s worth a quick look for oil mist build-up from the PCV system, cracked vacuum hoses, or a loose connector. If needed, remove it gently and give the sensing port a light clean with electronics-safe cleaner, don’t poke anything into the port and don’t soak the sensor.

Common symptoms of a crook or contaminated MAP sensor include:

• Hunting idle, flat spots, hard starting, or higher-than-usual fuel use
• Check engine light with codes like P0106, P0107 or P0108

Got a scan tool? With key-on, engine-off, MAP should read close to local barometric pressure. At hot idle, expect a significantly lower kPa reading, if it doesn’t change much, look for vacuum leaks before blaming the sensor.

When replacement is needed, stick with a quality OE-spec Denso sensor and a fresh O-ring. Fit it to a clean, dry manifold, seat it square, and snug the bolts evenly. After installation, clear any codes, reset fuel trims if your scan tool allows, and let the engine idle for a few minutes so the ECU can relearn. That’ll keep the Wish running sweet and economical.

FAQs

Where is the MAP sensor on a 2018 Toyota Wish?

On ZR-engined Wish models it’s fitted to the intake manifold, typically near the throttle body. Look for a small black sensor with one electrical connector and an O-ring seal into the manifold.

How can they tell if it’s the MAP sensor or just a vacuum leak?

A vacuum leak often causes a high or unstable idle and lean fuel trims, while a faulty MAP can show implausible pressure readings. Using a scan tool, compare MAP at key-on (should match barometric pressure) and at idle (should drop noticeably). If spraying around joints affects idle, that points to a leak rather than the sensor.

Does the Wish use both MAF and MAP sensors?

It does. The MAF is the primary airflow input, while the MAP sensor supports load calculation, EGR and altitude compensation, and provides redundancy. Both need to be healthy for smooth drivability and good fuel economy.