A/C question

[Porsche 935]

I fixed my a/c in my Carrera this year, all new lines. But have an issue with my S2000. Wondering if someone can help. Pressures were way off and I replaced the receiver dryer. All was good, but stopped working again. I have no history on car but a/c stopped blowing cold again. Do these pressures look like the dryer is clogged again or the expansion valve is bad. The lower pressure is at idle, the higher is when engine us is revved.

[Porsche 935]

[Porsche 935]

[walt]

What was the ambient temp? Could you be low on R134? Did you recharge by weight when you fitted a new dryer?

That pressure is so low it may be kicking your compressor off.

[Porsche 935]

Temp here is in 80's. Yes did charge by weight. Compressor was running. When I replaced the dryer, if you revved the motor pressures would go above 300 so I evacuated the system, replaced the dryer, and pulled a vacuum for an hour and charged system. Pressures were good and a/c blowing ice cold. Has run less than an hour the whole summer. Just turned it on this weekend while programming new engine management for idle and you could feel a hint of cold air when revved but nothing at idle. The dryer or expansion valve are frequent issues on these cars. Expansion valve is supposed to be a bear to replace.

[86 911 Targa]

The expansion valve is easy-peasy to replace on the 911.

However, it is not a common failure mode.

https://www.google.com/search?sourceid=navclient&aq=&oq=S2000+expansion+valve&ie=UTF-8&rlz=1T4GUEA_enUS570US570&q=s2000+expansion+valve+replacement&gs_l=hp..2.0l3j0i22i30l2.0.0.0.30367...........0.X AD-MQyUltE#spf=1572196453235
^^^^^
Link.

You are correct, it is buried......

Best,

Gerry

[Porsche 935]

I replaced the expansion valve, not as hard as I thought it would be. Evacuated the system, charged it . Blowing cold now and pressures back to normal. Found high side cap in fender well so some one been in there. Ordered another dryer, will run for awhile and then replace dryer.