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New e39 owner air con/heater problems. help please

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Hi, recently purchased a very clean BMW 525i Sport E39 Touring. Its a 53 plate 2003 model.

I have had a few problems with the car and was hoping that someone may have had similar problems and would be able to advise or help.

I took the car for a drive the other day and noticed that when i have my air con off but the temp set to 16 on both sides the passanger side blows cold air but the driver side is warm or hot. Also there is very little coming out of the rear vents in the armrest.

I had the air con recharged today and it blows ice cold when air con is switched on but when its turned off the driver side gradually heats up.

Also I noticed smoke coming through the middle vents after I had been for a drive. Had a burning oil smell. Anyone know whats going on?. I thought it was oil leaking from the rocker cover gasket

I have just bought new discs and pads all round, air filter, pollen filters, fuel filter, oil filter, sump plug and seal, rocker cover gasket set with oil seal and 15 valve screw seals, also 8 litres of oil. So I am hoping to get all that stuff fitted over the weekend. The passanger side disc hex bolt is stuck though so its on hold until i get that free. The head is stripped.

Anything else i should be looking out for?. Really only the air vents that are bugging me. Read it could be fan clutch, or aux water valve/pump?. Any help would be much appreciated. Not looking to spend a fortune though as I just shelled out ££400 on all the parts and the air con recharge.

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is there any difference in behavior when you switch the air recirculation to internal versus external fresh air?
(If you remove the pollen filter housing and it's hose going into the cabin you can see the actuator for the fresh air. Check if that works.)
Do the footwell or windshield vents work as expected when you set the air flow direction to the desired position?

If it is partly working then one or more actuator is broken but if none of these directional actuators work then it is likely the air conditioning module. I have seen broken wires in the module to the MI-BUS connector which controls these actuators. 3 wire connector.

"Read it could be fan clutch, or aux water valve/pump?"
I don't think so.

Cause for burning oil smell is usually an oil leak at the hot side if the engine which is the exhaust side.

I just realized that the fresh air / recirculated air flap motor is on a separate wire, not on the MI-BUS.
The MI-BUS has the left ventilation actuator, backpressure flap actuator, defroster flap motor, left footwell flap actuator and the footwell/rear compartment actuator motor.
Hi, just fully serviced the car. New rocker cover gasket, oil cover seal, 15 rocker cover screw seals, new oil and filter, air filter, pollen filters, new brake discs and pads front and rear. The car is running much much better now. Like a new car. Still got the fuel filter to fit will try get it done when i have a bit of time adn when weather is any good.

The air con seems to be working fine now. dunno if it was due to new pollen filters or that i had the hose to the filter housing off when i was changing the gasket.

The gasket was like plastic when i removed it. It split and cracked and was wedged in. Spark plugs were corroded too. Seems like it had not been very well looked after. The engine was pretty clean though. It must of been getting oil changes but not much else.

thanks for the help.

If I can help anyone out with brake changing advice or rocker cover help then just send a message and i can help you out.
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