- Issues with air conditioning operation.

Meanwhile, rubber-cased oil seals are used under conditions where a metal-cased seal can fail (for example, because of thermal expansion). Unlike the metal-cased type, these seals do not rust. Moreover, they can seal a lightly damaged housing better than metal-covered seals since, in high temperatures, rubber can provide a more stable sealability.
The perfect remedy for this is to use oil seal materials that are rated for the temperature of your application. Also, ensure that the elastomer is free from volatile constituents like waxes, plasticizers, etc.
Significance of the 99 Camry Oil Pump Seal:
Oil Seal in Motor:
PTFE Oil Seals - A relatively new and exciting oil seal, the use of polytetrafluoroethylene means that they can withstand dry or unlubricated operations. With a massive thermal range of -130ºC to +200ºC and a strong resistance to chemicals, they are considered to be the future of rotary shaft seals.
FPM

Also known as a Rotary Shaft Seal, Shaft Seal, Lip Seal, Elastomeric Lip Seal or any variation of these. It is a simple device for excluding dust, dirt, water or any other contaminant whilst retaining lubricant in rotary shaft equipment. Generally, it has been developed as a means of protecting the bearings of rotating shafts.