R33 timing fluctuating

[T-emppu]

Hi SAU,

My R33 (RB25DET) timing starts fluctuating at idle. Bigger problem IS when boosting, A/F Ratio went very lean!

Need help, please....!

Here In Finland anyone knows IS It CAS or what? (bc We don't share information) ?

 Stock r33 Inc.

HKS airduct

3 " catback exhaust

Cusco coilovers

Impul strutbar

[GTSBoy]

At idle it is more likely to be caused by the ECU using timing to control idle speed.  This happens when the IACV is too gummed up to work.

It could be that the CAS is buggered.  Bearing wear and shaft wobble make it impossible for the CAS to work properly.

[T-emppu]

Thank you. I am 99.9% sure that it is a CAS failure. Now I got the assurance. Can you tell why A / F Ratio goes to the lean at full throtle? Timing drops below or too few gas pressure?

Thanks A lot ?

[GTSBoy]

Lean mixtures almost certainly from lack of fuel supply.  Beyond that, no I can't tell you.  Put a fuel pressure gauge on it and load it up, see what it says.