Problem 2008 Prius A/C

Sounds like he totally hooked you up for that cat replacement. That's just about the cheapest you could possibly get a legit replacement installed for, anywhere. Doesn't sound like you've had any emissions-related issues since then, so I'd say your mechanic is a keeper for now.

Also it sounds like he's diagnosing the A/C in a fairly ordinary manner. Compressor won't be cheap, but there's a pattern of refrigerant loss leading to the compressor overworking itself to compensate for low pressure, resulting in compressor failure. Make sure you find and fix the original leak before hurting another compressor.

 

if your ac compressor is bad it will throw a code (and it's not a check engine light) You probably have a leak in the evaporator which is hard to verify since the factory oil doesn't have dye in it. Try putting in a charge again, if it cools then your ac compressor is fine otherwise there's a leak somewhere.

If the leak is bad that you will lose a lot of oil then it can damage the ac compressor, I got that same issue with my Camry Hybrid.. the evaporator was leaking and I just top it off every year. It didn't last, I have to replace the AC compressor and the evaporator core.

 

I top it off with refrigerant, since I have a small leak the top off lasted for the entire summer. Worst part is I didn't add oil every time I top it off and that destroyed the compressor. If I do add oil I won't know how much to add anyway since the leak is not visible. Adding too much oil is bad but it's better than nothing.

I DIY everything so I have no idea how much it cost if done on a shop, I bought a used ac compressor for $100, condenser with dryer for $90 and evaporator for $90. If the ac compressor grenaded, the condenser/dryer and expansion valve should be replaced since pieces of it will clog the system. So the parts alone are expensive. If the evaporator requires replacement then the dash should be removed to access the evaporator, this is a $$$ (thousands) job.

You can drive it without the ac working.

 

I hope they didn't put in a non-hybrid oil or dye on the compressor because that will short things out. Sometimes you have to pay for mechanic's stupidity.

They need to check the compressor if it grenaded and contaminated the system, otherwise it will not function properly. If it grenaded then you have to buy more parts.

 

The evaporators are a known failure point. Many people in this forum have had one fail. The one in our 2007 failed. It took the dealer many tries (service appointments) before they acknowledged "since it is leaking, and every place we can see is not leaking, and the only place we cannot see is in the evaporator, then it must be the evaporator". They replaced the evaporator and it stopped leaking.

Don't run a Prius A/C with a leak! Doing so will eventually destroy the compressor.

 

Wish it was true that this could be the best way to judge a shop......