325e Surges Under Acceleration/Engine Braking

[72ratcamaro]

Have an 87 325e that when I am accelerating I can feel it "surging" through the power. Also when I am engine braking it surges a little bit. Idles great with no surging at all. Just trying to figure out where I should start looking and get this fixed before I chip it.

Thanks

[Big Unit]

This was happening to me, at first I thought it was the air flow meter but it continued to surge under acceleration. But it would only happen after 2-3 minutes of driving from a cold start. Since oxygen sensors don't start working straight away I thought it I could be the oxygen sensor sending a crap signal to the dme resulting in the surging. Anyway changed the oxygen sensor and it fixed it. I think I read somewhere they are a serviceable item and should be changed every 60,000km