Car is hesitating when accelerating?

[E30_Narek]

UPDATE: So, I drove around a bit with my new O2 sensor and that seems to have fixed it. It doesn't have a wonky idle on hot starts or the hiccup/stutter on acceleration. Plus, the fuel economy has improved! The idle sometimes increasing from 800-900 on its own but I'm sure that's just a small vacuum leak.

[Cephas]

UPDATE: So, I drove around a bit with my new O2 sensor and that seems to have fixed it. It doesn't have a wonky idle on hot starts or the hiccup/stutter on acceleration. Plus, the fuel economy has improved! The idle sometimes increasing from 800-900 on its own but I'm sure that's just a small vacuum leak.

I hope this is solved for you, but just in case...

I had a very similar problem - car ran weird when warm and got worse over time. Got 1221 codes but no vacuum leaks. Also, had to be cranked over for a while before starting when warm. Exhaust was rich and MPG's were low...

It ended up being a leaking injector for me.

[E30_Narek]

I hope this is solved for you, but just in case...

I had a very similar problem - car ran weird when warm and got worse over time. Got 1221 codes but no vacuum leaks. Also, had to be cranked over for a while before starting when warm. Exhaust was rich and MPG's were low...

It ended up being a leaking injector for me.

Actually, all the problems it was doing before came back... I'll look into my injectors soon to make sure. But first I'm going to have it tested for vacuum leaks.