Chemical Smell In Cabin (R134a leak?)

[Daskuppler]

Hello Everyone,

 

I have a 2002 Impreza TS. The AC went out last Summer, I recharged it this Summer knowing that there was a leak somewhere. I recently started smelling a chemical Smell in the cabin with the AC running. I'm assuming it is refrigerant since I know there is a leak somewhere. I would assume it is coming from the evaporator, but I don't know that much about the system.

 

My understanding is that it is accessible from the glove box, is this true? Is there anything else I should look for when I tear it apart?  Could it be leaving from anything else? What else should be replaced? I was planning on relaxing all of the o-ring gaskets throughout the whole system just to be sure since the system has been purged.

Can I refill it myself with auto parts store canisters or do I need to pay a shop to ensure a proper charge?

[nvu]

You'll have to access it through the glovebox.  Take out the entire fan/duct assembly to make life easier.  Once you do that, there's a white cover with 3 or 4 screws holding it on.  It's in the rearmost center console, near the floor.

You'll be working around the passenger airbag, unplug the battery beforehand.  There's a single nut that hangs the fan assembly way up near where the airbag is.  Probably a cable bundle hanging from it.

The expansion valve is sandwiched between the evap and external lines, when putting it all back together, get a helper to push on the engine side while you push from the cabin side.  Try not to depend on the tiny bolts to pull everything together, it's easy to crossthread them.

Other common places for leakage are the orings on the compressor and wherever there's a rubber hose to pipe coupler.

[Daskuppler]

18 minutes ago, nvu said:

You'll have to access it through the glovebox.  Take out the entire fan/duct assembly to make life easier.  Once you do that, there's a white cover with 3 or 4 screws holding it on.  It's in the rearmost center console, near the floor.

You'll be working around the passenger airbag, unplug the battery beforehand.  There's a single nut that hangs the fan assembly way up near where the airbag is.  Probably a cable bundle hanging from it.

The expansion valve is sandwiched between the evap and external lines, when putting it all back together, get a helper to push on the engine side while you push from the cabin side.  Try not to depend on the tiny bolts to pull everything together, it's easy to crossthread them.

Other common places for leakage are the orings on the compressor and wherever there's a rubber hose to pipe coupler.

Thank you for the tips! So it's not really necessary to replace the valves and o rings unless the seal is taken apart?

[nvu]

Yeah, the orings far away from the compressor rarely fail if left untouched.  Though if you already loosened them, might as well replace them since you're there.  Get an oring assortment box from wherever is convenient.  The expansion valve, probably a quick glance will tell if you need a new one.  If it's gunked up, looks corroded, just pick up any generic one that fits.  You could try freezing it to see if it closes, it's probably not worth the effort.

Oh the schrader valves could leak, though those are easily replaceable and can be done anytime.

[Numbchux]

All the Orings are in the engine bay. The only place the refrigerant would be leaking that's inside the cabin is a hole in the evaporator itself.

Also, there isn't a lot of refrigerant in the system. A volume that you would be able to smell would only last a few minutes. I doubt that's your issue.

[Daskuppler]

19 minutes ago, Numbchux said:

All the Orings are in the engine bay. The only place the refrigerant would be leaking that's inside the cabin is a hole in the evaporator itself.

Also, there isn't a lot of refrigerant in the system. A volume that you would be able to smell would only last a few minutes. I doubt that's your issue.

So what would be a possible cause? I know there's a leak in the system somewhere, but if it's not likely to be in the cabin, what could cause the smell?

Edited August 9, 2021 by Daskuppler

[Numbchux]

1 hour ago, Daskuppler said:

So what would be a possible cause? I know there's a leak in the system somewhere, but if it's not likely to be in the cabin, what could cause the smell?

 

Depends what you're smelling. Could be anything. My guess is something more potent, like antifreeze, gasoline, or something dripping onto the exhaust.

[Daskuppler]

1 minute ago, Numbchux said:

 

Depends what you're smelling. Could be anything. My guess is something more potent, like antifreeze, gasoline, or something dripping onto the exhaust.

It's definitely not anti freeze, no sweet smell. It smells similar to axle grease, but nowhere near as potent. I'll check the cabin filter and look around the engine bay and see if I can find anything.

The car does have an emissions cel that comes and goes along with an issue filling up with gas (the pump auto shuts off at about 2 gallons if left at full flow).

[1 Lucky Texan]

look for split CV boot. That grease is smelly, more so if slung onto the exhaust.

GL5 is the most smelly fluid, really stink do, possible front diff, manual trans I guess....?

[Daskuppler]

12 hours ago, 1 Lucky Texan said:

look for split CV boot. That grease is smelly, more so if slung onto the exhaust.

GL5 is the most smelly fluid, really stink do, possible front diff, manual trans I guess....?

Good call on the CV boot, the axles are fairly new, but there was a small hole in the passenger one.  That accounts for the smell, now I just need to find the leak.  I'm working on another vehicle at the moment, but I'll delve into this one shortly.