Hello. I'm trying to locate the low-side charging port to my '97 ford explorer. I'm in Phoenix, AZ and a friend informed me to use R-134a to my explorer to increase colder air. Need your assistance. Thanks.
The low side charge port should be on or near the reciver/dryer on the passenger side near the fire wall under the hood. Before ***** nilly throwing freon into the system however, you should be sure that the current charge is low. One common indicator is a fairly rapid periodic cycling of the A/C compressor on and off when the controls are set to cooling using the A/C. Also if you put some ing, at least get a charge kit that has a pressure guage for the low side. Your friend is correct in that the 97's were after the OEM systems began using R-134a as the refrigerant.
JerrySimm is correct... make sure you check the pressure before adding any freon. Read the instructions that come with the kit. I'm not trying to sound like a smart alec, but I've seen people just grab a can and cheap hose from Walmart or Pep Boys, shove it in, and end up overcharging the system which can result is some costly repairs.
Overcharging typically results in a loss of cooling performance because the suction side pressure will be higher than it should be. Remember, on the suction side of a properly operating system the pressure is around 35psi and also note that at this pressure the temp is approx the same as the pressure. I've seen people overcharge and end up with 48psi on the suction side....and they wonder why "it's not working right". Modern systems use what is known as a "critical charge"; if you're paying attention to your gauges as you charge you will notice that once you hit the correct charge and begin to add a bit more, the suction side pressure will begin to rise. It doesn't take much to see this; depending on the system three ounces and you will notice this. In this case, purge the slight overcharge and you'll know the job is done.