My 2007 Cooper S, 90k miles, has no heat. I took it to the shop anticipating a bad thermostat or clogged heater core. The coolant level is fine, no leaks.

The mechanics went over the car for two days, eliminating the obvious and more.

Now they want pull the dash, in an attempt to diagnose the problem. I am now looking at a $800 bill, and counting.

I'm looking for advice on any possible causes and cures. I've gone through the board, it looks like a fairly typical problem, but usually with a typical solution.

Any advice is greatly appreciated.

-David

 

Was there any repairs done to the coolant system? There is a bleeder screw on the thermostat housing that could remove any trapped air in the system. If you weren't low on coolant, I would not expect to have air in the system, though.

I have read people getting an error code for the thermostat stuck open, but you didn't mention this, so I would not think this is your issue either.

Did they change the thermostat? For $800, on a 6 year old car, I would expect that this should be done. Did they actually do anything?

I'm sorry that I don't have any silver bullets. The system should not be that difficult to diagnose. If there was a water pump issue, I would expect an overheating issue.

Good luck,
Mike

 

Hi Mike,

Thank you for your response. They told me that they could not get a fault code. THey have not changed out the thermostat -- yet.

The $800 is for dash removal and diagnosis ONLY -- it does not include parts or labor associated with replacing defective parts.

At this point they suspect that the blending doors are not operating properly. Does the dash need to be removed to get to the blending doors?

 

I would think that you would want to confirm if hot water is actually getting to the heater core. If there is hot water going in, and warm water going out, then it is likely a problem under the dash. If the water going into the heater core does not get hot, then it would be something else. Here is how I see it:

Water flowing into (and out of) the heater core when the car is on full hot. if this does not happen, then either the heater core is blocked or the control valve is not working. If water is flowing into and out of the heater core, then the problem is that the water is not hot.

If the water is not hot, and the coolant level is fine:

1. Air trapped in engine (there is a bleeder valve on top of the thermostat)
2. Thermostat not working properly.

The thermostat is a known problem on these cars as they get old. The housings can crack, the gaskets can leak, or the thermostat can fail (resulting in a car with no heat). I would strongly encourage the technicians to change the thermostat before pulling the dash for 'exploratory surgery'.

Mike

 

Hi Mike -- I spoke to my mechanic again. He confirmed that hot water is entering and warm water is exiting the heater core. The car has no issues that would indicate a problem with the thermostat - the car comes up to appropriate temperature and does not overheat. There are no signs of leakage. And of course no fault codes.

I am dropping the Mini off on Thursday for the repair. I will once again ask questions about the thermostat before the exploratory surgery.

Thanks again for your help.

-David

 

I would hope a mechanic with a flashlight and a mirror or even a flexible camera would LOOK to see if the damper doors are working....heck the "inspection" video cameras are getting very cheap...heck habour freight has them advertised for around $100-150....seems like a useful item for most any pro shop to have around.....

 

Quick update --- I now have heat. The problem was a badly clogged heater core -- which the mechanic was able to address without removing the dash. Mike your questions helped here -- thank you again.

-David

 

How much did the repair set you back? On many cars, you have to remove the dash to get to the heater core..