1jz surging

[triptek]

I'm having a little problem with my jza70. When cruising along at 1500-2000rpm, it will sometimes start surging up and down 3-400rpms. It doesn't do it in any other part of the rev range. I'v checked for error codes and it's showing no problems. And the surging goes away when I start accelerating.

Anyone got any ideas what it could be.

[pato]

i had a surging issue on idle
was fuel related, either a cloggage, or the fuel pump was on its way out or something, i cant remember,
it was weird like that too, it worked fine while driving along but when idling it was retarded,

worth a check if u cant figure it out i guess

[JZA70 R]

i had the exact same problem but i had it with the power fc installed.

it was the o2 sensor feedback. i turned that feature off on the power fc so it was open loop, and that resolved the problem. i dont think it was a dead o2 sensor but its possible. more than likely the o2 sensor feedback wasnt configured properly.