Evaporator small leak

After I fully charged the AC:
run the car for 10 minutes, turn it off, wait 5 mins, stick the sniffer in the drain tube and it starts chirping.
After about 30 minutes it will stop chirping at the drain tube.
Start the car again for 10 minutes with AC, turn it off, wait a couple mins, and its chirping again.
Shined UV light at drain tube and no dye found.
Removed blower motor, stuck borescope in ac box and did not see anything obvious on the front side of the evaporator.
Repeated process above, stick borescope through blower motor, no chirp.
Tried to remove the ac drain tube to get borescope in there but the scope cant see anything.
Can it be leaking from the back of the evaporator where I cannot see it?
Having a tough time getting a camera on the back of the evaporator.
Can I stick it through one of the vents? Which vent is the shortest distance to it?
I would like to see a visual confirmation of the leak before ripping the dash apart

Here's a video:
https://youtube.com/shorts/eJRd0_baG3Y?feature=share
Did the sniffer test several times from above and below the car.
Chirped every time in the conditions above, even if the sniffer is not directly touchign the tube

 

Do you smell an oil or abnormal smell in your car when you start the car/ac?
I just had an evaporator core leak and it took a while to actually find it. The mechanic couldn’t even find it himself but my car would smell strange when I got into the car. Big issues with 2nd gens and the evap core.
paid 1250 for parts+8 hours labor. Would have done it myself but dont have the time anymore to pull the dash and all day job.

 

Oh my! There goes the idea of keeping the gen2 truck forever.

 

Why? That's like 3 or 4 months of payments on a new one.

Those of us who enjoy our older trucks, and want to keep them healthy, would be silly not to be setting aside funds for planned maintenance and unexpected repairs.

 

No, I don't smell freon coming out of the vents. I suspect its a pretty small leak

 

Welp, I did. And that’s currently being funded for the check engine light shambles on her!

 

I'm ordering OEM evaporator and some OEM seals. Only $70 for both from the dealer. Then about another $20 for a freon charge.
I guess the cheap parts help lighten the blow of having to tare the entire dash apart

Also found suction line to be leaking at rubber hose crimp as well as shraeder valve.
this line was aftermarket garbage and i will be replacing with OEM
liquid line leaking from shraeder valve before and after I just replaced the valve, so getting a new liquid line too. OEM line is well-priced
and finally a new dryer desiccant since system will be apart

at this point, the entire AC system will have been replaced except for the compressor and discharge line