this may help w R134 a/c.
eng. off
lo=90
hi=90psi
eng idle cond. fan off
lo=25
hi=140psi
center vent temp=68f
eng idle cond. fan on
lo=25
hi=140psi
center vent temp=66f
eng idle cond. fan on
add 1 can r134
lo=35
hi=230psi
center vent temp=46f
eng 2000rpm cond fan on
lo=28
hi=250psi
center vent temp=45f
i invert the can for "liquid".add for 10 sec. close wait for 2mins, then repeat until the can is empty.take your time.
hiway,mid day center vent temp=53f, city vent temp=63f it sux.

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72 250 CE-5spd-gone
79 280 CE
82 300TD
83 300 CD
83 380 SEC