AC Issue

This morning my AC starting blowing a white, misty smoke. For those of you who have been around them, the odor was like a fogger machine that bands use or for Halloween parties. It did not smell like burning oil or rubber. I checked under the front hood and nothing, nothing in the engine compartment either. The car is otherwise running fine. Good oil pressure, good ampere reading, good engine temp, smooth idle and drives fine. It seems like when I put it on recirculate, it does not smoke but by the time I got that far, the car was so full of smoke it was hard to tell. Compressor on or off does not seem to matter. Defrost or main vents does not seem to matter either. Any ideas? Thanks, JKC

With no smell or other signs of a A/C leak reads like the cool air from the A/C is encountering the warm moist air in the cabin and creating a mist/fog. Be sure the body water drains under the front trunk lid are clear and there is no water collected. Also, you might want to have the A/C checked -- or check it yourself (I don't know to get to this) -- the evaporator pan/drain (whatever there is under the evaporator to collect the water condensation that forms and falls down) -- is not holding water. Let me add that you might consider before shutting off the engine for the day/night running the A/C system with the A/C compressor off for a few minutes but the cabin fan on to help dry the evaporator and the A/C air passages/vents.

I will run the A/C with compressor off. I used to do that in an old car that was prone to develop mildew but had gotten out of that habit. Got ahold of my mechanic by email. He says sounds like evaporator may have sprung a leak. There is more than just mist/fog, it has an odor, just not an electrical or burning oil or burning rubber smell. What say you? And thanks for the reply. In Livermore, CA it must be "... dark-thirty" right about now. JKC

For those interested... After further "... diagnostics" and head scratching and internet research, I think my problem is a leaking heater core/heat exchanger or whatever the proper term is. I went outside to start the car and let it run a bit since it has not been run regularly in 2 weeks. With the A/C compressor on, and the temp set to "lo" there is no smoke. (It is in the 30's here in Atlanta). As soon as I put some heat on the system, the smoke starts up. Compressor on or Off... No matter. Whenever I call for heat, it smokes. When I drop the temp back down to "lo" the smoke clears out and eventually stops. Doesn't matter if I am recirculating or venting... And the interior is glass is now covered with an oily film. These are exact symptoms as posted elsewhere. And recall, I said the smoke did not smell electric or mechanical... Now that I think of it, it does smell like burning coolant. Good news is that I do not have to remove the dash to get to the heater core (it comes out at the front of the trunk) so I am going to pull it myself next week and have a look. (Seems to me that if it were an A/C evap. core, it'd blow smoke with the compressor on... Not off, and then , it'd eventually run out of refridgerant, and blow clear. I am guessing the compressor would then drag and ultimately seize? I am experiencing the opposite with the smoke appearing, and it is getting thicker, not thinner). In any event, I've already bought a replacement car because I was planning on selling the 996 but the thought of selling so cheap is still less appealing to me than getting hit across the face with a wet fish. The plan now is to slip into DIY mode for all but the most complicated repairs (or those that require special tools). This is a little daunting for me because the cars I've maintained myself were a '69 Cougar, a '66 Mustang, and, an '83 Rx-7... All, decidedly less complicated. Nevertheless, I do have a mechanical mindset and a basic understanding of cars... So, I'm going to give it a whirls. Bentley manual any good? I share this detail for those who will experience similar symptoms, for those who may have a pointer or two to share, and , for those following a 996 with 215k on the original engine. Say a prayer for my soul and if you are not religious, rub your rabbit's foot for me. Details to follow in a week or so. If anyone wants PICs, let me know and I'll try to remember to snap a few. Take it easy, and hope everyone is otherwise doing well, JKC

A 996 with 215K miles and a leaking heater core is going to bring about $1.98 on the used car market. If the car is in otherwise good shape -- and to be running at 215K miles it probably is -- it is cheaper to fix the heater core and continue to drive the car. The Bentley manual is ok. If you can find them the factory manuals are good to have. Used to be able to download these from a UK web site the site name I have long forgotten. You can't be the first one to have to replace a heater core in one of these cars so a search should turn up posts by some who have gone before you and possibly even put together a DIY on this subject.

Macster... A few things... First, you are absolutely correct on market value. I'd be better off dismantling it and selling pieces over the course of a year or so. Seriously, from what I am hearing, people want to pay me about two or three times what the rims and tires are worth. It has been wrecked but properly repaired and is in great shape... Especially for its age. Second, found a tutorial on removal of the heater core. Not too difficult. Third, thanks for the feedback on Bentley. I'll probably pick one up anyways. Most of the stuff I'd be doing is pretty lightweight... Regular maintenance type stuff. I just found out AutoZone will take my spent oil if I buy it from them, so... Oil changes, Filter changes... Stuff like this heater core, maybe alternator if the belt isn't too much of a bear and plugs and stuff. We'll see. As posted, I bought another car (albeit, lackluster) so I can take my time with projects and still get to work and stuff. In any event, thanks for your feedback. You are among a select few who consistently post on here with helpful feedback and it is appreciated. Hopefully, someone will read my miscellaneous ramblings and get some insight if and when they face a similar problem. (I get the feeling I may be pushing the envelope for mileage on these and other folks will start to see my issues too). Take it easy and have a good week... And rub that rabbit foot for me. JKC

What happens when/if you shut the engine off, carefully remove the radiator cap ( (no coolant pressure) and now run EVERYTHING...??

Quotes source post: 11081615

But check hose connections at the firewall FIRST.

WWest, Thanks for the feedback... What would that tell me? When I ran the heater and did my "... shadetree diagnostic" the car had been idling for about 10 minutes and up to temperature. When I first noticed the smoke, I was starting to Church in the cool morning and it seemed to get progressively worse as the car warmed up, but I turned around and came home pretty quickly. Hose connections at firewall outside in the trunk, or inside in the footwell or behind the console? I haven't started digging into the heater core yet because I haven't had time... Will probably do so this weekend, but I can run your tests if you tell me what they might mean... Thanks for the feedback. Really appreciate it. If I'm ever in Redmond, Washington I'll buy you a beer. (Don't hold your breath on that one)! JKC

Sorry to be unclear... What would taking off the radiator cap and running without pressure tell me? Thanks, again, JKC

"..progressively worse as the car warmed up..." the hotter the coolant the more pressure you will have in the system. Any leak would provide stronger outflow leakage with higher coolant pressure. The hose connections at the firewall are easy to check/tighten. Replacing the radiator cap is relatively inexpensive since the one you have might not be relieving system pressure properly.

OK... So, you are saying a bad radiator cap may be over-pressurizing the system (not venting at the correct pressure) and I should check cap and then hoses? Then, pull the heater core? Where are hose clamps? Under dash/console or in trunk? Thanks, again for all your feedback. It helps. JKC

And the radiator cap is probably as old as the car and may be failing... Needing replacement. One last question... When I get into this, can I use regular coolant or do I need to buy Porsche or some other European brand? I don't buy into the "... name brand" crap but just want to make sure the alkalinity isn't different for Porsche (or there isn't some additive because of a composite or alloy bearing or something. Thanks, JKC

There is quite a bit of info on rad fluid choices if you do a search. Good luck, and let us know how the repair went...pictures always welcome. 2003 Carrera 4S Speed Yellow / 1955 356 Continental 1500 Rust Red