[s-cars] Low rpm stumble

[George Verbryck]

I am having a curious problem at first I thought it was a coil going bad ( 1.8 coil conversion) But I checked and replaced the coils with no effect. When I am cruising on the highway and try to overtake without down shifting I get a serious stumble . If I select a lower gear problem goes away or is much less noticeable. Recently it has become worse where almost any lower rpm sprint produces similar results once 3500 rpms arrives problem dissipates to redline.  Thanks for any insight, George