how do I fill in freon for 2001 4runner ?

any clue as to fill freon in 2001 4runner ? Is it the r134 ? I have the hose to fill the freon but no pressure guage. Just one can enough ?

yes it is r-134. There may be a site glass on the accumulator. When the system is full you should see no bubbles through the site glass. Start with one can and see if there are any bubbles.

You can get an inexpensive pressure gauge for under $10 that will get you in the ballpark.

If you're sure there's a leak, add refrigerant that also includes a dye to help find the leak. Also, if the gauge reads zero when you first connect it, then the system has been fully discharged. Depending on how long it has been like that, you will proabably need to replace the accumulator/drier and apply vacuum to remove all the air inside the lines before adding any refrigerant. This will prevent ice buildup inside the lines by removing all the water that has gotten inside.