Where's the low pressure canister - Cars & Trucks

code p 0300 refers to random/ multiple misfires detected ===causes --spark plug/s--HT lead/s--injector/s --ignition coil/s--low compression --wiring
most likely low fuel pressure and injector problems
code p 0442 refers to evaporative emission (EVAP) system ---small leak detected ===causes hose connection/s--intake leak-- EVAP canister ---EVAP canister purge valve
it also refers to --large leak detected ===causes ---petrol cap loose ,/missing---mechanical fault ---EVAP pressure sensor
code p 0455 refers to EVAP ---large leak detected --all those stated plus EVAP canister purge valve
code p1680 refers to electric throttle control (ETC) monitor ---processor fault ===causes --wiring--ECT monitor

Maybe a clogged valve on canister

The low pressure cycle switch is located under the air filter housing. It is attached to the accumulator drier. the drier is a canister with two aluminum lines and this sensor attached to it .

Along the condensor lines, you will find 2 ports that should have screwed on black caps, you will then remove the cap. Dependant on the year, you may need to upgrade the system R-12, vs R-134a; and recharge kits are available at various locations depending where you live. Also, the AC system is charged based on pounds, so be extra careful when attempting a new charge. Some vehicles only require 2 lbs.

Look at the lines (aluminum) and the size of the lines. The low pressure line is the bigger of the two where as the smaller line is the high pressure side. Normally the low pressure Schrader Valve is nearer the radiator just up from the canister dryer.

The a/c has a low pressure port on the low pressure side of the a/c piping system.

One can identify the low side by looking at the 'thicker' pipes vs. the 'thinner' pipes on the high pressure side.

There may be a canister that has a low pressure port on it on the passenger side. Or else, it's on the thicker piping itself.

There may be a blue or black cap on the port.

The pressure should read 35psi to 45 psi on the low side when the a/c clutch is spinning or engaged.

When the a/c clutch is not spinning or engaged then the pressure should read 75 psi to 100 psi on a hot day.

turn ac on with engine running check for power at the compressor if there isnt check for power at the low pressure switch if there is jump out the connection
the compressor should turn on the low pressure switch is usually located on the accumulator canister (SILVERY CANISTER) near the firewall.

it will be on the ac lines. the smaller line is the high pressure line and the larger line is the low pressure line. it is probably near the canister shaped part that the aluminum lines to into.

low pressure is coming from the dryer, the canister on the passenger side of fire wall. The high side is next to compressor.

Check hoses for cracks and holes at the pictured locations