SharkSkin

You should have been able to see it through the pollen filter slot when you had it out.... maybe with the help of a strong light and a mirror...

Randy V

I see!

So if I can see it, why can't I clean it without removing a bunch of stuff, Dave?

SharkSkin

Maybe you can... but what I was suggesting is to take a look through the pollen filter slot. You might be able to spray a liquid cleaner in there if it's just a bit dusty. But if you have leaves, candy wrappers, and misc. pedestrian body parts in there, you'll probably have to pull the HVAC blower to get them out...

Steve J.

Use ester oil compatible with both. Charge with R-134a. If it cools good, you're all set. If it leaks, not a big expense if you have to open the system up. You can buy R-134a at WalMart. If it holds pressure and you're not happy with the temps, you can always recharge with R-12. R-12 works a little better but I don't think there's a lot of difference based on my experience with both.

dr bob

What Dave said...

My thinking is that the pollen filter, if it's doing anything for you, should be filtering out the dust before it turns to mud on the evaporator. Candy wrappers and cigarette butts should all be on the dirty side of the pollen filter, right? The only dirt that should make it to the evaporator is from recirc air from the cabin, if I understand the airflow map correctly.

Randy V

OK, Bob n Dave - I guess my evaporator should be relatively clean compared to non-pollen filter equiped cars.

Thanks.

Herman K

If your car has a pollen filter with an access door all you need to do is check the filter and through the access opening you can spray in the cleaning agent.

I did not realize that my GTS had the filter set up installed until I had done the fan and airbox removal. I had done this ones before when I had a 90 S4 which did not have the filter or access door.

Ones I had removed the vallence cover that keeps the fan and wiper motor out of view, I found that while owned by the PO the entire area must have collected tree leaves over a long period of time. There where so many leaves that the fan outside air intake was blocked by leaves and they even hampered the wiper motor and arm rotating smoothly. So in order for me to remove all the leaves from all areas and to repair the seal on the recirculating flap I had to remove the fan and airbox any way. Today I drove the car in downtown Houston [ 94 degree outside] and inside the car I measured an evaporator outlet temprature of 38 degrees, fan speed at #2 and temprature slide set at 70

HK 94 GTS

Randy V

Aha! That's a good piece of info, Herman.

So, even with a pollen filter, was the evaporator on your GTS in need of cleaning?

SharkSkin

Keep in mind that anything can happen in 10+ years -- stupid POs -- a torn filter might have been left in for an extended period, the filter may have been left out for an extended period.... The only way to know for sure whether your evaporator is clean or not is to look. Obviously, odds are better on cars that have the filter but ya never know...

Randy V

Cue the Jeopardy theme music. Herm?