Low pressure valve for ac - 1994 Buick Skylark

In general the Low-pressure valve is a safety feature to protect the A/C compressor from damage. The valve can be changed without too much effort, sometimes the spring inside can become weak and activate at a different pressure than designed. With strong grip, it can be changed by hand, using care not to twist the a/c lines it is mounted on. It has an electric connector which has clips to secure it and they must carefully be unlatched.

There are 2 valves which are similar in appearance and the low-pressure part is closest to the black oval tank or even mounted on the black oval tank. You want to be sure to change the correct one. This will only help you IF the original part was defective.

When this part is working properly, it prevents the A/C from working when the Freon is low. If the Freon is low there are many possibilities why this happened. Each car is an individual case. Depending on the size and location of the leak, sometimes an additive in a new can of Freon with a sealer/conditioner can help. Sometimes too much air leaks into the system and it needs to be purged and you start over fresh.

Autozone has loaner tools to create a Vacuum in the system, measure the pressure in the Freon lines and do other repairs. It is a free program with refundable deposits.

You can go to an autoparts store and ask to see the correct part. The clerk may even look under the hood of your car to show you where it goes. If the valve is bad, replacing it can fix the problem.

You should not lose but a whisper of Freon when switching this part. But if the part is good, you need to address the low pressure. Freon has gone up so much that a mistake is costly. Use to be that you would try adding Freon first to solve a problem when Freon was $2.50 a can.

Also watch for the size of the can of Freon. Many shady ads will sell you short cans of Freon at a "discount" price. You pay less but get less.

Since each car must be judged by inspection results, its a specific call on what to do.