AC Not Cooling - Blocked/Stuck Expansion Valve (TXV) Replacement

Body/Interiorintermediate✓ Community Verified

Problem

AC system not cooling despite compressor running and clutch engaging. AC lines to and from compressor are not cold. Gauges show abnormal readings with the low side pulling into a vacuum when AC is turned on.

AC blows warm air despite compressor running and clutch engagedAC lines to and from compressor not coldStatic pressure reads 50 psi on both high and low side with AC offHigh side rises to only ~75 psi when AC is turned onLow side drops into a vacuum when AC is turned onSmall bubbles visible in sight glass on dryer

Root Cause

The expansion valve (TXV) becomes blocked or the needle gets stuck closed or near-closed, preventing refrigerant from flowing through the evaporator. This was a known issue on 89-92 models when Toyota changed to a newer block-style TXV used with the parallel flow evaporator design. Toyota issued a non-expiring service campaign for 89-92 models for this issue.

Confidence

Moderate confidence — Multiple community members agreed on this solution

View Original Thread →Posted October 2023 on SupraForums.com