Parts for your 1993 Mitsubishi Pajero-Tx valve

1993 Mitsubishi Pajero TX Valve – What it does and how to look after it

Technical references including the Mitsubishi Pajero/Montero V20 Workshop Manual (Heating & Air Conditioning section), the Mitsubishi ASA electronic parts catalogue for the V2/V3/V4 series, and Denso service literature confirm the 1993 Pajero’s air-con system uses a thermostatic expansion valve (TX valve) mounted at the evaporator. So yes, a TX valve is relevant and fitted on this model.

The TX valve’s job is to meter liquid refrigerant into the evaporator, responding to evaporator outlet temperature and pressure. By keeping the evaporator just shy of icing, it maximises cooling while avoiding liquid slugging of the compressor. On a ’93 Pajero—many of which were R12 from factory and later converted to R134a—the TX valve is a core control component and a common culprit when cabin temps aren’t behaving.

• Typical TX valve symptoms: weak cooling at idle or all the time, evaporator icing, rapid cycling, high or uneven pressures, and a frosty or unusually warm line at the firewall.

As part of regular servicing, it’s smart to have an A/C specialist check pressures, vent temps, and for any staining around the evaporator connections—especially on vehicles that see corrugations or outback tracks. Age, moisture ingress, and contamination (metal fines from a failing compressor) can stick or block a TX valve.

1. If replacement’s on the cards, have an ARCtick-licensed (AU) or appropriately certified (NZ) technician recover the refrigerant—releasing gas is illegal.
2. Access is typically via the passenger side: the TX valve sits on the evaporator at the firewall, with lines passing through the bulkhead. Removing the glovebox and parts of the evaporator housing is common practice.
3. Always fit new O-rings, use the correct refrigerant oil type and amount for the system, and replace the receiver–drier any time the system is opened.
4. Flush lines if contamination is suspected, then evacuate for an adequate period to boil off moisture. Recharge by weight per the under-bonnet label, not by guesswork.
5. Finish with a leak test and verify superheat/pressures to confirm the new valve is metering properly.

A quality TX valve from an OE supplier (often Denso on the Pajero) and good sealing practices will restore steady, chilly air and keep that V20 comfortable from city traffic to alpine tracks.

FAQs

Where is the TX valve on a 1993 Pajero?
It’s mounted on the evaporator at the firewall on the passenger side. Access is usually from inside the cabin by removing the glovebox and evaporator housing, the refrigerant lines connect through the bulkhead from the engine bay.

Should the receiver–drier be replaced when changing the TX valve?
Yes. Any time the system is opened, the drier should be renewed to capture moisture and debris. Skipping it can shorten compressor life and upset TX valve operation.

Is the 1993 Pajero R12 or R134a, and does that affect the TX valve?
Many 1993 models were R12 when new, with plenty since converted to R134a. The TX valve must be compatible with the refrigerant and oil in use. Check the under-bonnet label, if converting, follow proper retrofit steps and charge by weight.