Hunting idle after startup

[El Andrew]

Anyone seen this before? About a min after startup, idle starts hunting - sounds like it's got a big cam in it. You can see on the wideband the AFR is all over the place. Ignition timing is about -4 degrees

 

After about a minute of that, it settles down to a steady idle and behaves itself, goes back to a more normal +15 ignition timing at idle.

 

Has always done it occasionally but seems much more frequent lately.

 

I should data log the cam angle sensors.

 

[eff xr6t]

Do a log with fuel source tq source and all the normal rpm cam angle. My guess is you will see the fuel source change to cylinder cut whilst it is running like that

[El Andrew]

Thanks mate I'll do that and see what it shows

[eff xr6t]

Have you currently got it running in open loop for tune testing?

[El Andrew]

Nup

[Rob Smith]

check coil packs...a mate is just asking if he should replace the lot after he had the same problem and found one coil pack is crook.

[El Andrew]

Thanks mate. Has brand new genuine coils and was doing it with the old ones so not that in my case I don't reckon.

However... I've replaced a few things as part of a refresh over the last few weeks and the issue seems to be gone. Cam sensors, crank sensor, O2 sensor and throttle body clean - must have been one of them! Although maybe it was changing the diff oil...