Parts for your 1990 Mitsubishi Pajero-Maf sensor

1990 Mitsubishi Pajero MAF sensor

Short answer: it depends on the engine. Technical documentation shows that a mass air flow (MAF) sensor is used on 1990 Pajero models with petrol electronic fuel injection (Mitsubishi ECI-Multi), notably the 3.0L V6 6G72. Carburetted 2.6L 4G54 petrol engines and the 2.5L 4D56 diesels of that year use mechanical fuelling and do not employ a MAF, so for those variants a MAF sensor isn’t relevant.

Technical sources referenced: Mitsubishi Pajero/Montero Factory Service Manual (circa 1989–1991), ECI-Multi section describing a Karman vortex-type air flow sensor, Mitsubishi ASA electronic parts catalogue for 1990 Pajero V6 models listing “Sensor, Air Flow” in the EFI intake group, and Haynes/Max Ellery workshop manuals for 1983–1996 Pajero noting an airflow meter on EFI petrol models and none on carburetted or mechanically injected diesels.

If the 1990 Pajero is an EFI petrol (e.g., 3.0 V6), the MAF sensor is central to how smoothly it runs. Sitting between the airbox and the throttle body, the Karman vortex-style meter measures the actual air mass heading into the engine. The ECU then trims fuel and ignition so it starts cleanly, idles nice and steady, and doesn’t drink more litres per 100 km than it should.

On these older Mitsis, owners often notice flat spots, rough idle, black smoke, or poor economy when the MAF is dirty or the intake has leaks. Before binning the sensor, it’s worth a few easy checks under the bonnet:

• Look for split intake hoses, loose clamps, or a perished airbox seal—unmetered air will make it run lean.
• Inspect the MAF plug and wiring for corrosion or brittle insulation.
• Clean the sensor carefully with proper MAF cleaner only, don’t touch the sensing grid or use aggressive solvents or compressed air.
• Avoid oiled filters that can coat the sensing path.

If cleaning and leak checks don’t sort it, a replacement MAF is the go. Choose quality OEM or a trusted aftermarket unit that matches the ECI-Multi spec for your engine code. Fitment is straightforward: disconnect the battery, swap the meter, ensure airtight joints, and reconnect. After replacement, let the ECU relearn by idling for a few minutes and then taking a gentle drive cycle. If the vehicle supports it, check for stored fault codes using MUT/OBD1 procedures to confirm all’s sweet. With a sound air filter and intact intake plumbing, a healthy MAF will give thousands of kilometres of reliable service.

For carburetted 2.6 petrol and 2.5 diesels of the same year, there’s no MAF to service because fuelling is handled mechanically or via manifold pressure and governor systems rather than measured intake air mass.

Popular questions

Does a 1990 Pajero have a MAF sensor?
Yes, if it’s an EFI petrol (like the 3.0L V6 6G72 with ECI-Multi). Carburetted 2.6L petrol and 2.5L diesels don’t use a MAF at all. If unsure, check whether your intake has an electrical sensor housing between the airbox and throttle body.

Where is the MAF on the 1990 EFI petrol Pajero?
It’s mounted in the intake duct right after the air filter box, ahead of the throttle body. You’ll see a rectangular aluminium or plastic housing with a multi-pin connector and an arrow indicating airflow direction.

Can a dirty MAF be cleaned or should it be replaced?
Often a careful clean with proper MAF cleaner restores performance. If cleaning, wiring checks, and intake leak fixes don’t help—or the sensor fails frequency/voltage tests per the workshop manual—replacement is recommended.