Four Seasons 91800 HVAC Heater Core

Four Seasons 91800 Heater Core for Toyota Camry

The Four Seasons Heater Core 91800 is an aluminum HVAC heater core built to match the listed Toyota Camry applications. With OE-style dimensions and direct fitment for 1997-1999 Camry models, it supports reliable cabin heat transfer in a compact, vehicle-specific design.

Key Features

• Brand: Four Seasons Heater Core
• Part number: 91800
• Aluminum heater core construction
• Core dimensions: 8-1/2 in. length, 6-1/2 in. width, 1-1/4 in. thickness
• Core height: 8.500 in.; core width: 6.500 in.; core depth: 1.250 in.
• Tube size: 0.625 in. / 15.875 mm on both tubes
• Meets or exceeds OEM requirements
• Compatible with 1997-1998 Toyota Camry and 1999 Toyota Camry built to 8/98

Product Details

Four Seasons 91800 is part of the Heater Core product line and is engineered as an aluminum heater core for HVAC service. The compact core size and OE-matching specifications make it a direct replacement choice for Toyota Camry heating system repairs where the original core has leaked, restricted flow, or lost heat output. This part cross-references APDI 9010393 for the same application.

Fits 1997-1998 Toyota Camry, N/A. Fits 1999 Toyota Camry, N/A, to 8/98.

Common Issues This Part Can Address

• Weak or inconsistent cabin heat
• Coolant odor inside the vehicle
• Fogging caused by heater core leakage
• Loss of heater performance from internal blockage
• Coolant seepage at the HVAC core

Installation Notes and Tips

Verify the vehicle build date before ordering, especially for 1999 Toyota Camry applications noted as to 8/98. Compare the original core dimensions, tube size, and pipe orientation before installation. Because heater core replacement often requires HVAC case access, inspect related hoses, seals, and coolant condition during service.

Quality Assurance

This Four Seasons heater core is listed as meeting or exceeding OEM requirements and is built to the dimensional and material specifications shown above. Confirm fitment against the vehicle application and part number 91800 before installation.