Is it possible to remove and re-install the A/C expansion valve from the engine side of the firewall? This would include replacing the o-rings associated with it. -Thanks

 

This is a 2007 ES350. Easy to remove expansion valve and replace o-rings. Remove the strut cross member to give yourself access. One bolt removed allows you to pull the refrigerant tubes. Then removed two 4mm hex bolts securing the expansion valve to the evaporator. Pull the expansion valve. inspect for problems (in my case I was looking for an o=ring leak on the expansion valve-evaporator interface). replace o-rings with new ones. Assemble is reverse of tear down. Torque specs (from repair manual) are 30 in*lbs for the 4mm hex bolts holding the expansion valve to the evaporator, 87 in*lbs for the bolt that holds the refer tubes in place, and 63 ft*lbs for the bolts that hold the front strut cross member in place.

Alas, this is not the source of my leak. leak detector indicates presence of refrigerant in this area on both the engine side and the cabin side of the firewall. was hoping for something easy before pulling the dash out to get at the evaporator.

 

Thanks for adding me. Got a 2007 RX350 with locked up compressor. 160K miles. No gas left in system. Belongs to #1 son. Need it for another year, then its gone.

Trying to DIY replacement system from UAC with help from a pro who will dry and recharge system. Need to replace expansion valve (LVX)which seems to be on side of evaporator (left side?) on interior. Wish was on firewall but doesn't seem to be the case. What's the quick and dirty way to access LVX? Life too short to take dash apart. And once removed, do you flush evaporator from the interior by adding a drain tube to tub outside vehicle? After that, I think we can handle the stuff in the engine compartment. Whew....

Understood this is an old tread, but did'nt see specific threads regarding this. Any advice much appreciated. This car is turning into my Great White Whale!

Thanks!
Mike

 

On the 2007 ES350 you can replace the expansion valve from the engine side of the firewall.