I’m a month in to new ownership of a 1989 FJ62 and am still working to sort the AC out. When I bought the truck the AC was blowing cool but not cold, my mechanic charged the system (it has been converted to r134a previously but I don’t know any details about when or how thorough the conversion was) and mentioned the expansion valve seemed to be sticking. He replaced the expansion valve (OEM part) and I’m still in a similar situation where the AC intermittently blows cold but is mostly just cool (about 5-10 degrees cooler than with AC off).
I’ve figured out that most of the time my compressor clutch is cycling very rapidly (stays on for just a second or two, off for a second or two and so on) which of course makes cooling the air a challenge. When the clutch does stay engaged, which happens sporadically, the AC blows ice cold (about 40 degrees). My mechanic went thru and charged the system again based on specs I got from Mud, as we thought low Freon may be causing the issue and there were bubbles in the sight glass of the drier. With the system perfectly charged the frequent cycling is still occurring, when the clutch switch is bypassed the clutch stays engaged no problem so not an issue there.
He suggested I may need a new low pressure switch but before I go replacing another part I was hoping to get some input from you guys. Does a faulty low pressure switch seem like a possible culprit? Can the low pressure switch be changed without affecting the charge in the system (I.e. is this something I can do myself pretty easily)? Also is the part listed below correct? Thanks!
I’ve figured out that most of the time my compressor clutch is cycling very rapidly (stays on for just a second or two, off for a second or two and so on) which of course makes cooling the air a challenge. When the clutch does stay engaged, which happens sporadically, the AC blows ice cold (about 40 degrees). My mechanic went thru and charged the system again based on specs I got from Mud, as we thought low Freon may be causing the issue and there were bubbles in the sight glass of the drier. With the system perfectly charged the frequent cycling is still occurring, when the clutch switch is bypassed the clutch stays engaged no problem so not an issue there.
He suggested I may need a new low pressure switch but before I go replacing another part I was hoping to get some input from you guys. Does a faulty low pressure switch seem like a possible culprit? Can the low pressure switch be changed without affecting the charge in the system (I.e. is this something I can do myself pretty easily)? Also is the part listed below correct? Thanks!
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