Exhaust header color

[DonE]

I just pulled my header to coat them and noticed that the right side (4-5-6) header had a frosty white exhaust coating while the left side was black. Can this be a tuning problem? It seems odd that all three stacks are colored at the same time.

Could the injector bank have a problem in the wiring?

Could the electromotive DFU's be messing with that side?

The car runs great - idles and accels just fine. AFR's are nailed.

Thanks

[DonE]

It seems to be a fuel delivery issue - where is the fuel being introduced and on which side of the regulator.

[cstreit]

What fuel are you running.

Brownish White is good if you are running racegas... Means overly lean on regular unleaded.

[DonE]

The color is off-white and will not rub off when touched (it reflects an environment of high temp). The other side is carbon black and it barely rubs off when touched - what I would call normal using pump gas.

[DonE]

Here is a pic of the exhaust port with streaking on the valve.






Here are the plugs from #4 (left) and #1 cylinders for comparison.



Comments?

[cstreit]

The plugs look pretty good... Again, seems like the left bank is lean... Check your fuel rail on that side maybe?