On my 91 it is on the pasenger side close to the firewall. under a brass cap
The low side will be on the accumulator and the high side will be on the discharge line.....
The low pressure side of any AC system begins at the metering device outlet and ends at the compressor inlet.
left side on firewall should be on the side of ac condencer
low side is next to or on conpressor.has blue cap on low side red cap on highside
On the receiver/dryer.
You recharge your vehicle ac system throught the low side port. All vehicles are different as where the low side port might be located. There is a website www.idqusa.com that has helpfull information about your vehicle ac system including where the low side port is located on your 00 f-150 .
In front of the radiator
ac drain stopped up,ac is low on freon
Its on the accumulator/drier. You can find a drawing of this on the link below. Just follow the "Find Your Car's Low Side Port" icon.
The low side ac port for the 1990 e 150 should be on an aluminum pipe. The pipe is on the passenger side of the engine compartment just beside of the battery.
Yes, if you recharge it on the high side, you could blow up the can using to recharge it. So it is very important to use the low side.
Its on the Receiver Drier/Accumulator. I found a drawing of it on the site listed below.