Why is my 2001 BMW 530I giving me a headache from heater fumes

I am getting pulses of a smell from the dashboard vents that smell like burning oil. If the windows are closed, you get a headache that accompanies the burning oil smell. My wife told me that the car smelled like someone was smoking in the car after i drove it for a half hour. I have had all oil leaks in the engine fixed and the engine steam cleaned. There was no burning oil smell under the hood after the last trip and no sign of oil leaks on the engine. Therefore, I don’t believe that the smell is coming from the engine compartment. The heater box has been cleaned and leaves and other debris removed. The smell is not continual. It comes in pulses, almost like a pop, but no noise.
I would like to be able to drive this car, but need to figure out what is causing the problem. Any and all suggestions please

“Headaches” makes me suspect exhaust fumes – very dangerous (to people, not to the car). Sometimes we confuse various smells around the car.

Could the “pulses” be a leak at the exhaust manifold, perhaps on one cylinder (i.e. one pulse on the exhaust stroke of that one cyl, rather than a downstream leak that would give one pulse for every cyl’s exhaust stroke)?

I’d think you would be able to hear such a leak in the engine compartment. Time for guys more knowledgeable than me to chime in.

It could be a blower motor going out.

The exhaust system is tight. Had not thought about the blower motor.

I’ve no doubt you had the exhaust system checked, but before calling it “tight” you may want to pick up a CO monitor for the car. CO is way to dangerous not to make absolutely certain that you’re not smelling exhaust fumes, and CO monitors are cheap.

In the end. I hope it does turn out to be the blower motor. If you can remove the motor (it’ll be mounted into the side of the ductwork under the passenger side dash) you can bench (table) test it easily. Attach two 12VDC lantern batteries to it in series and it should spin fast, smooth, and quiet. If it’s the motor, you’ll smell it when you test it. Perhaps even when you remove it.

tsmb – two 12V batteries in series?? Did you mean two 6V batteries in series, or are you deliberately running the fan motor at 2X normal voltage?

Also, if you meant to run it off 12V (not 24V), I would just use the handy car battery – use a cig lighter plug adapter, or open the hood and clip-lead it to the btty.