If you check the pressure on the low pressure line and it is very high then you should make sure the compressor is ON. You may have put the blower on, but on the dashboard there usually is a button that turns on the ac compressor. When the comp is on the pressure will drop into the "blue" range. This is the first check, and the simplest
The high pressure line is a high pressure hydraulic line. The can leak from the attachments to the fittings. The will leak where the line is damaged Or if it as a very old line they can crack.
super hard shifts
A leak somewhere in the system.
Possibly a pressure reducing valve installed after piping for first faucet, which would cause situation describing.
A bad fuel pressure regulator or a clog in the fuel return line that leads back to the tank will cause this.
They may be marked "S" and "D" for suction (low side) and discharge (high side). A simpler way would be to look at the lines going into and out of the AC.... the smaller line will be the high pressure line, while the larger line will be the low pressure line. The low pressure line will connect at the compressor inlet, and the high pressure line will connect at the compressor outlet.
High discharge pressure and low liquid line pressure
No, the liquid (discharge) line is the high pressure side. The suction line is the low pressure side.
High pressure line gets very hot.
When you say too high, just how high is it and what is the high side pressure. It is not uncommon for the suction pressure(lowside) to get up to 80psi on a very hot day. You cannot determine what is wrong unless more information is provided. It could be that your system is overcharged, but without the high side pressure and the temp of the suction line it is hard to give the right answer.
Lots of stuf can cause it including sediment or a blocked supply line
It don't have a low pressure valve. the high pressuer sensor is in the high pressure line next to the raditor. It don't have a low pressure valve. the high pressuer sensor is in the high pressure line next to the raditor.