Wildly varying vent temps

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Wildly varying vent temps

Postby za105 » Fri Jul 06, 2018 12:11 pm

This morning at 10am, engine cold still, I got into my 1998 Jaguar VDP and blasted the A/C, recirculating (it was cooler in than out) and full blast through the face vents. Vent thermometer read 39-40 degrees, and indeed, it was ice cold, despite outside temps of 80+. I quickly turned the air off and rolled windows down and sunroof back for driving around. No need for icy air with such moderate warmth.

This afternoon at 2pm, after the car sat with the engine off for two hours, the car was very warm in the sun with outside temps reading 93. I got in and quickly evacuated the hot air by lowering the rear windows and sun roof, and turning recirculating off. After a couple minutes of driving, I shut the windows and sunroof and blasted the air, recirculating on. 65 degrees out of the vent!

I’ve now been sitting in a relatively cool parking garage for ten minutes, A/C blasting, and the air is STILL only 65 degrees through the vent.

Any ideas what’s going on? Since it gets ice cold SOMETIMES but other times refuses to even go beyond cool, I’m lost. Especially annoying that it shows itself to be capable of super cold air when I don’t really want it, but when it’s actually hot out it completely sucks and goes up 35 degrees at the vent.

Do I need to insulate the pipes under the hood? I hear mixed things about this, but perhaps they’re getting too hot after driving around.

Refrigerant can’t be a problem, right? After all, it gets freezing cold sometimes.

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