vibrating Blower Fan

Been trying to get my AC working good and waiting for a couple adapters to check pressures. Meanwhile I added a couple cans of R134a and it helped a little.

Yesterday going to the store I turned the AC on and the fan to high, a couple minutes later BAM! loud noise and I felt vibration all through the car. In a panic I shut off the AC, went into neutral and finally shut the blower off. That was it, the blower fan out of balance. It was like someone threw a bananna into the fan, very heavy vibration in all speeds so I kept it off.

Rolled the windows down and went about my business, checked the blower several times and it was still badly off balance. Between thinking what could have happened and how I will go about replacing it pretty much consumed my mind. Anyways a couple hours later on the way back home I threw the fan on again and there was no vibration, like I imagined it all. On comes the AC and drove the whole way home with no issues.

So what actually could have happened here? A mouse trying to commit suicide and failed and ran back out? I don't think there is any easy way to take a look in there, can it be done? I have one of those cameras on a stick to hook up to a laptop, where would I gain access? Can I check through the cabin filter access?

Have seen a mouse in the cage of someone before. But I also had a blower fan where the cage was too old and brittle and the plastic broke. In any case you have to get the blower motor out to inspect it.
Here https://www.bimmerforums.com/forum/s...or-Replacement

Egads, doesn't look real fun with the V8. I will hope whatever it was does not return.

with the V8 it is still easy. "the fun starts" when you own an E32 750 with a M70 engine in the engine bay

K got the new fittings and tested, very low so I added an additional can of R134. Brought it up to 30 low side and 128 high side. Should be at ambient 45-55 and high side at 250-270 This is with 4 cans 12 oz! Guess I need to buy a couple more cans. (pressure measurements are guestimates from memory But it is still low).