Parts for your 1992 Mitsubishi Pajero-Tx valve

1992 Mitsubishi Pajero TX-valve: purpose, care, and when to swap it out

Referencing technical sources such as the Mitsubishi Pajero/Montero 1991–1996 Workshop Manual (Group 55: Heating and Air Conditioning), the Mitsubishi ASA electronic parts catalogue (V20-series evaporator/piping diagram), and common parts catalogues from OE suppliers like DENSO, the 1992 Mitsubishi Pajero is fitted with a thermal expansion valve (TX-valve) at the evaporator inlet. It’s a TXV/receiver-drier style system rather than an orifice-tube/accumulator setup, so the TX-valve is absolutely relevant on this model.

On a ’92 Pajero, the TX-valve meters refrigerant into the evaporator based on superheat, keeping the coil cold without freezing and making sure cabin temps stay stable even when the weather swings. Think of it as the brain of the A/C—feeding just the right amount of refrigerant so the system cools efficiently while protecting the compressor.

Typical signs the TX-valve’s not pulling its weight include:

• Weak or inconsistent cooling, especially at idle or after a hot soak
• Frosting on the evaporator lines or erratic vent temperatures
• High/low side pressure readings that don’t track together, or rapid cycling
• Hissing at the valve area or contamination/debris seen during service

On the Pajero, the valve sits at the evaporator inlet behind the dash (commonly accessed via the glovebox area). Any work on the A/C must be done by a licensed air-con technician—refrigerant recovery and charging require proper equipment and, in Australia, ARCtick-authorised handling. If the system’s opened, best practice is to replace the receiver-drier, renew all O-rings, and evacuate and recharge to the correct weight. If the compressor has failed or the system shows debris, the TX-valve should be replaced rather than cleaned, and the system flushed as appropriate.

For vehicles originally on R12, many in AU/NZ have been converted to R134a. Matching the correct oil type and quantity (and valve specification) is critical. A technician will also re-insulate the sensing bulb/valve body, torque fittings to spec, leak-test, and verify superheat and pressures. Done right, a fresh TX-valve can transform a tired Pajero A/C—colder vents, happier compressor, and far better performance in Aussie and Kiwi summers.

FAQs

Where is the TX-valve on a 1992 Pajero?
It’s mounted at the evaporator inlet inside the cabin, typically accessed by removing the glovebox and trim to reach the evaporator case. From there, the valve and its sensing bulb are right on the evaporator pipework.

Can a TX-valve be cleaned, or should it be replaced?
If contamination is minor, a technician might attempt cleaning, but sticking or corrosion usually calls for replacement. If there’s compressor debris, replace the TX-valve and receiver-drier and flush the system.

What maintenance helps the TX-valve last longer?
Keep the system leak-free, renew the receiver-drier whenever the system is opened, and ensure correct refrigerant charge and oil type. Regular professional checks of pressures and performance go a long way to preventing TX-valve issues.