Intermittent A/C not blowing cold air issue

This is almost always due to a low charge of Freon or a compressor issue.

So we need to start with checking the level of the high and low side.

Here is a guide that will help with this:

https://www.2carpros.com/articles/re-charge-an-air-conditioner-system

We need to make sure we use a gauge set and not just the plastic gauge on those refill cans to determine of the pressure is correct. Unfortunately those are not only not accurate but not meant to diagnose a system. They are just meant to help not overcharge a system.

Also just pushing the valve in on the low side is not going to tell you if the pressure is correct either as you can have 2 PSI and get Freon to come out but you need upwards of 45 PSI on the low side when the compressor is on.

So let's get the pressures and go from there. However, I am attaching a chart below that will give proper pressures for the R134 system and possible issues when the pressures are outside this range.

Let me know what questions you have.

Thanks