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Toyota corolla 2005 ac blows cold on high revs


Topic starter

I recently purchased Toyota Corolla 2005 japanese made automatic transmission with 150000 kms on it.

My car ac only works when I drive on high speed or accelerate. I tried to fill the freon but all in vain. The ac mechanic told me its compressor is weak bcoz low side shows high psi. Btw this is the my third car the ac mechanic unable to repair despite changing with scrap compressor. I had to sell my previous cars having the same issue.

There is no code, no leakage anywhere too. Besides I never saw the car dripping condensation water too. 

I love the car but I cant drive without ac as I live in a very hot area.

Running pressure checked with manifold are

40 psi on low side

140 psi on high side

Ambient temp

46*C . Humidity 10%


2 Answers

I don't know what that equates to in real temperature, but those pressures are too low when running in a hot environment.

Note that the charge level is critical and needs to be within a few ounces of specification. Too little refrigerant would lead to low pressure readings and no cold air. It is also possible for an expansion valve stuck closed to cause low readings and lack of cooling. Inoperative condenser fan would cause no cooling when the car isn't moving but pressures would climb.

Since you say you are getting cold air at high rpm that does suggest that a weak compressor is most likely. Replacing one 17-year-old compressor with another old "scrap" compressor was probably not the best approach.

It sounds like you need to go to a different AC technician. There should be many to choose from in a hot area.

Thanks for your respond Chuck.

Chuck today I tried to add freon in my car as now the ac dont cool at all, while at high rpm, the compressor was tripping but was not cooling at all.
Does that indicate a different problem?
My car is toyota 1.5L 1nz fe engine with automatic.

What were your system pressures before and after adding refrigerant?


As I said before the charge level is critical, you should not be adding refrigerant blindly.


You might also try diagnosis by checking temperature at various points in the AC system.