Bumbling stumbling 89 535iM

[New2BMW]

Good morning all,

Bit of a wierd and worrisome problem has cropped up in my new-to-me 89 535i manual, with 175,000 on the clock. Yesterday, after no previous issues of the sort, the car began exhibiting a hesitation and stumbling under acceleration (even mild acceleration), culminating in some severe stumbliness on the highway. Got home, thank goodness, and took a look at the cap and rotor. Sure enough, both appeared heavily carboned up, and the person at the Pep Boys counter pointed to what he said was a crack in the cap before handing me the $80 (I know) Borg-Warner replacement cap and rotor. Installed, tested the car, it was like a different car!

Unfortunately, the stumbling returned this morning, though not as severely as yesterday. What happened to last night's flawlessly smooth operation?

Since this problem only cropped up in the last couple of days, might I have a bad tank of gas, or some other fairly obvious thing? Anyone else experienced these symptoms and know the cure?

I also did the stomp test, got code 1222, but don't know if the two are related.

Thanks in advance for your help!

[peks]

1222 is o2 sensor and yes its related to bumbling and stumbling..