Hey group - I have a 2017 F56 MCS 6 speed that is exhibiting a couple strange issues. I'm asking for input one at a time to eliminate confusion - I'm easily confused. Below is today's question.
Background: I bought it used with about 23,000 miles on it. I commute across Florida every week, so I'm putting about 30,000 miles on it annually. It's been fine until I had a minor (< 5 mph) accident hitting someone who stopped after starting to turn right on red. Yes... my fault... dumb rookie mistake... mostly minor damage. The body shop replaced the radiator, intercooler and condenser among other body and bumper parts.
Problem: Here in FL my A/C runs almost 100% of my drive time. It works fine to/from work and all the "around town" driving I do. It blows nice and strong and cold. The problem occurs after a couple hours of driving across the state. The air stops blowing strong and decreases in the strength of the "blow" coming out of the vents. I can hear the blower running, but it's not coming out of the vents. I dial up the fan, i can hear it, but nothing more comes out the vents. Changing to the windshield defrost, or lower vents, or combinations doesn't help. What little air I can feel still feels cold. it's only after hours of driving (at speed, always in sport mode). There are no warning lights or check engine coming on the dash when it happens. The next day everything is fine and working properly again. And 1 more thing, it doesn't happen every trip across the state...? This all started after the car was in the MINI and Gieco approved body shop.
Any suggestions, recommendations or hints are appreciated. Before I take it to the dealer and likely have them want to replace everything, I thought maybe someone more experienced than me may have some thoughts.

 

Recommend you run (or have someone run) a scan to get all codes out of the car. Here's the gotcha: standard OBD-II scan is only going to get you certain codes. You want *everything*.

Have you ever used a Bluetooth OBD-II adapter and have you ever used BimmerLink?

 

I haven't used the Bluetooth OBD-II with BimmerLink, but have read plenty about them here. Sounds like it may be time to make the investment and get some answers.

 

now let me get this straight, it works fine around town in Fl. but screws up after an hour or more on the road ? sounds like a vacuum - vent problem but start with the filter first. I think it's related to the little middle direction button - windshield/vent/floor. what setting do you have your fan on ? I usually have mine on 4 (the little dial light is at the top)

 

Check for leak sign. A common leak point is (believe it or not) at the low pressure/high pressure Schrader valves. Often these are replaced when the system is evacuated just on general principles.

But leaks can be at other places, too. New condenser? Well, the install may have been botched. Or the condenser is bad. Often for an accident repair the shop will use aftermarket parts not factory parts. Generally one is better off with factory parts.

Even if you spot a leak this is not a driveway job to fix. The car needs to be taken to a qualified shop for A/C servicing.

To replace the condenser the A/C system should have been evacuated to remove any refrigerant. (I had a car hit and the condenser just damaged but not holed so the system was full of refrigerant.)

Then the new condenser is installed and the system evacuated again to remove any moisture (carried in when the system was opened to outside air). At the same time the system is checked for large leaks. (A leaking Schrader valve will probably not show up as a "large" leak which is an argument for just replacing these.)

If the system appears leak free and the system has been under vacuum for long enough to ensure no moisture remains the system is refilled with the proper type of and amount of refrigerant. And the compressor oil amount is topped up. A condenser replacement results in some loss of compressor oil. A factory condenser should come with some oil in it. An aftermarket condenser probably comes dry.

Then the system is given a check out to ensure it blows sufficiently cool air and the low and high pressure values are within spec.

The loss of cooling after time rather than suggesting a system low in refrigerant to me reads more like water in the system is freezing and blocking refrigerant flow.

A check of the pressures would be done -- if the system is low on refrigerant the pressures would be wrong -- and if found ok then the system evacuated. Could be the tech would want to replace the receiver/drier which may have been overwhelmed by moisture/dirt in the system arising from the condenser replacement.

Then the system is evacuated and checked for leaks then refilled with refrigerant and oil then checked for correct operation.

 

Hey guys, thanks for the suggestions and recommendations. All seem to have merit and may lead to the source of the issue. I've suspected it may have to do with the body shop doing mechanical work in the car. I'm most interested in getting it resolved as opposed to finding blame. With your suggestions I can at least have the dealer start to eliminate some of the possibilities.

And yes, Stu-mon, it's fine around town in Florida. The problem occurs after at least an hour on the road and gets progressively worse until almost no air is being moved out of the vests.

 

Is it that the air coming out of the vents isn’t cold, or is it that the air coming out of the vents slows down and the air volume isn’t there? (Like the fan is slowing down)

 

FWIW I read this from the first post:

as an airflow/air volume-related description (which is what made me think of chasing codes, because that boils down to a blower, opening/closing vents, and dynamic control systems for both).

 

do you run the MAX AC button or just the AC button ? I'm in Fl. & run my temp. on 70, & recirc. button on A & my AC button on, no MAX. I'm happy, I did notice a change in the recirc. button when on the road for awhile but that was on M. why have fresh warm air come in at all I say.I run Recirc. on 24/7 but on A. with ALL buttons OFF I think it vents to Outside Air.

 

Been years since I have manually selected recirc mode. I think it might be active if I hit the defrost button. But my cars are garaged and they leave the garage with clean ice freeze glass.

As for a change in the recirc button I seem to recall at least with some cars that if one selects recirc mode this is disabled after some time. By recirculating the cabin air, which is cooler than the outside air, this can result in the evaporator icing up. Also, years ago the few times I experimented with recirc mode I seem to recall fogging of the glass was a problem. Not right away but after some minutes.

With cars with manual or auto climate control I just set the cabin temperature to 72F and if the system supports auto climate control I enable the mode (or just turn on the A/C compressor) and the A/C works just fine. Keeps the cabin comfortable when driving through 119F heat or 0F cold (after the engine is warmed up...).

 

I think using recirc might be relevant, perhaps try not using it for a day or two... But I'm thinking the fan resistor pack is over-heating after long use. Can you manually select the highest speed, because that should bypass the resistors altogether?

 

Personally, I would start with checking and/or replacing the cabin air filter. The charge on the A/C system could be low, certainly, but the cabin air filter is a pretty easy DIY.

 

FWIW, can confirm that on my 2017 Cooper S, manual recirc is disabled after a certain timeout (I believe I read in some BMW spec-thing or discussion of same that it was 10 minutes, and that seems to line up with my experience.

Can also confirm that fogging of glass when recirc is on is an issue, most notably if someone else is in the car. That's not unusual for any vehicle in my experience, but my MINI does seem to be decidedly consistent about it.

Finally, can confirm that fogging of glass is an issue with recirc+humid conditions (even without recirc on, this is the case in humid conditions).

That said, in general my MINI does not behave as the OP describes as being a problem. When the fan is on AUTO, I have seen some decidedly unexplainable behaviors about how the raw volume of air is handled. But having the airflow simply dial itself down unexplainably -- only a handful of times, confirmed by me turning it off and on again and getting more air without changing what I set the dial to. I *have* had a sometimes-code (801228, "Power management: Reduction of fan power") -- still trying to figure out what triggers that, it's on the rare side of intermittent and doesn't usually accompany symptoms I notice, so it's tough to chase.

But in general what OP describes does not sound to me like normal AC behavior, normal effect of recirc use/nonuse/setting, etc.