beatupjeep
02-20-2015, 08:38 PM
So..this is probably a clue but I'm not sure how to interpret it.
Air conditioning works GREAT. You can go out into the 115F desert and crawl around at 3000rpm and it blows freezing cold to the point where you need to actually turn it off. Meanwhile the coolant temp is right in the middle of the gauge.
Problem is, sometimes the clutch will just stop cycling. Nothing else changes. Blower still going, engine revs go up a bit to where I think the computer sets it for high idle when AC is on.
After a few years I figured out that if I switch to neutral then rev the engine up to near redline for a second, the AC clutch will re-engage and everything will be back to normal.
So what does that all mean? Seems like maybe an AC clutch issue? But I think I measured the AC clutch voltage when it was stuck off, and there wasn't any voltage at the AC clutch.
So maybe the pressure switch in the AC is getting stuck/frozen, and the high rpms just rattle it around? I suppose I could test that by whacking it with a stick instead of revving the engine?
89 cherokee 4.0 manual
Air conditioning works GREAT. You can go out into the 115F desert and crawl around at 3000rpm and it blows freezing cold to the point where you need to actually turn it off. Meanwhile the coolant temp is right in the middle of the gauge.
Problem is, sometimes the clutch will just stop cycling. Nothing else changes. Blower still going, engine revs go up a bit to where I think the computer sets it for high idle when AC is on.
After a few years I figured out that if I switch to neutral then rev the engine up to near redline for a second, the AC clutch will re-engage and everything will be back to normal.
So what does that all mean? Seems like maybe an AC clutch issue? But I think I measured the AC clutch voltage when it was stuck off, and there wasn't any voltage at the AC clutch.
So maybe the pressure switch in the AC is getting stuck/frozen, and the high rpms just rattle it around? I suppose I could test that by whacking it with a stick instead of revving the engine?
89 cherokee 4.0 manual