Best automotive expansion valves & parts according to redditors

It's just one of the many variants of a line piercing valve. See another one with similar features here: https://www.amazon.com/Robinair-40288-Piercing-Valve-Tubing/dp/B000J4KQAQ

[Line Piercing valve] (https://www.amazon.com/dp/B002YKJWT4/ref=psdc_15723781_t1_B000J4KQAQ)

I think you need this tool

https://www.amazon.com/Assenmacher-Specialty-Tools-TOY-200/dp/B000FL9C58/ref=pd_lpo_vtph_469_tr_img_2?_encoding=UTF8&psc=1&refRID=5GCZQVCYHYRC812PCDNF

I am not an A/C system master, but have read up on them a little when I was shopping for an E30 without A/C...

First of all, your E36 uses R12 refrigerant (pg 640-11 from the Bentley manual), but this unnecessary information. Before anything, take your car to an A/C shop and have them flush your system completely, this should be free because they can resell the refrigerant (If not pay you for it). Then do a leak test with a can of dyed r134a using a conversion kit fromyour local autozone/advanced auto/oreilys/etc. Something like this below.

http://www.amazon.com/Interdynamics-320-Retrofit-Kit/dp/B001AIZLQY

And then most people recommend replacing the expansion valve as well.

http://www.amazon.com/dp/B0019ILOF2/ref=asc_df_B0019ILOF24310609?smid=ATVPDKIKX0DER&tag=shopzilla0d-20&ascsubtag=shopzilla_rev_121-20;14643263694201161168710070301008005&linkCode=df0&creative=395093&creativeASIN=B0019ILOF2

Not sure on the accuracy of this information! But good luck! I got lucky with my E36 being R134a!

I've redone the entire AC system myself after my compressor 'ate itself alive'. The proper way, is to replace everything. The reason for this is because of what you eluded too; the metal shavings. I opted to replace every single line (high and low), the compressor, and the expansion valve.

Once you have all new components you need to add the oil. The amount you add is dependent on how much is in the compressor (or the whole system). There are a few guides on this and HELMS manual has a calculation you must do. For sanity's sake, if you're close, you'll probably be alright. However, full disclosure, I am no HVAC expert.

• You can use a compressor if you have one but you'll definitely have to remove every single component to ensure you get every single nook.
  
• It might be. Remove it from the firewall and take a look. They're pretty cheap if you have to pick one up. I bought this one and it's been running fine for years.
  
• No. Aside from a new serp belt if it's showing signs of wear.
  
• You're right. Having this done by a shop is the only right way. They need to evacuate your entire system once you have it all sealed up. Then put new freon(whatever it is nowadays) into it. Then charge it to the proper PSI. (as i understand it).
  
  You can do ALL of the work yourself save for the charging/recharging/evacing.

LR027661

https://www.amazon.com/gp/product/B00TTBCAU4/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

The rig and r410a would easily exceed the cost of just replacing it. I already have a vacuum pump so omitting that cost.

Manifold gauge
$47 - Flexzion Ac Refrigerant Manifold Gauges
HVAC Air Conditioning Charging Service Set PSI Kit Halogen Diagnostic Tool for R22 R410a R404a with Three 60" Hoses in Red Blue Yellow https://www.amazon.com/dp/B01792INPU/ref=cm_sw_r_cp_apa_i_28PhDbPCF009A

$76 - R410a 28oz
https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.com%2Fulk%2Fitm%2F202654527468

$7.23 x 2 - bullet piercing valve, one for high side, one for low.
Supco BPV31D Bullet Piercing Valve https://www.amazon.com/dp/B00J2D6OEC/ref=cm_sw_r_cp_apa_i_.bQhDbV62YH63

Already about $140 before tax

I was just trying to find a cheap ersatz solution.