Highly likely they're mufflers. I have one on my car's suction line and it's supposed to keep the reed valve noise from reaching the evaporator. Fails miserably, in my case. Here's a pic.

I described how my car's VDC+TXV system works. That's the most it will attain with a blue (42+-1 psi) MCV fitted inside. It will never give you vent air that is colder than 41F. And it will sense discharge pressure, use it to control how cold the evaporator will get and give you 41F at vent only in ...

I'd say 41F, or 42F at most. Above that, it's highly likely you've got a problem somewhere (mostly either a ridiculously low refrigerant charge or a worn compressor), even though it will still appear to provide some cooling (but 46F at vent tends to feel rather warm in my experience). Get below that...

Good to know. Mine came from a Kia car. Hyundai part number 97604-17001. Manufactured by Daehan Koki. Delphi SP10 fixed displacement swashplate compressor. The orifice's diameter makes me think of a 1.5 TR rated valve. The fact that it's still open a little once the disc is like -22F, on the default...

You mean this one? As i said before, don't touch it. If you touch it, you've basically tampered with the valve and you won't be able to return it. You might also ruin your compressor. Aside from cross-charge power heads, superheat is a really complex thing in MVAC. Your suction line needs to travel ...

Agree - definitely sounds like the valve superheat is too high for some reason or its orifice is a bit smaller than intended and as a result tonnage is lower than required. In fact many automotive TXVs are specifically designed so that the evaporator never gets starved during the cycle, even at real...

Even in milder climates, if you have a variable displacement pump, it'll be getting louder as the evaporator runs progressively more starved and the superheat increases as a result. At this point, hearing what sounds like what you get when you try to drink through a straw from an empty McDonald's pa...

I hope this will clear things up. Look at these valves (second hand ones i've bought to play around with/flush my evaporator in case i want a new compressor). The one on the left is a Daehan Koki (Hyundai PN 97604-17001). The one on the right is a Denso 447500-1600 (Toyota PN 88515-52010, Suzuki PN ...

I'd like to chime in with something about the TXV. Rockauto.com shows Denso 475-2046 as the recommended TXV for your car. However, Denso part 475-0511 shares the same Toyota OEM part numbers and is used with the same type of Denso scroll compressor (only slightly smaller displacement) on a number of...

1)25 minutes is too short of a vacuum. Vacuum for at least 1 hour. 2)Condenser can't be flushed if parallel flow. Must be replaced in that case. Did the old compressor seize up? 3)Suction pressure is abnormally low. Sounds like the evaporator is being starved of refrigerant, provided it isn't freezi...