3.2 Rebuild: Carbon in exhaust port

[TT Oversteer]

Just recently rebuilt my 3.2 with new everything (no expense spared). It's now fully broken-in with about 1500 miles on it. I pulled the exhaust today to install my header exhaust system and discovered two exhaust ports are quite black, especially compared to the others. I'm not entirely sure if it's a result of oil getting past the guide or from a rich running condition in that cylinder. I'm not sure what to make of this since the engine runs well and doesn't smoke. If it's a rich cylinder I'm not sure what could cause only one in that bank to behave differently than the others unless it's maybe a stuck injector (they were cleaned & tested). In the pics it's #2 that's black and #1 slightly black. All others look as I think they should. Opinions please.....

[ant7]

Could be injector spray pattern not right, hence the cylinder isn't firing optimally' or the injector is weeping and not closing properly causing it to run rich, get the injector tested first before worrying yourself prematurely that it could be something more drastic!
Hope this helps.
Anthony.

[Ferrino]

How long did the injectors sit after cleaning? I was told that you shouldn't leave them idle for too long after cleaning or they can stick. Just a suggestion...

[Trackrash]

If you pull that cylinder's plug you may be able to determine the source. If there is oil causing the problem it may be evident on the plug.