Ramanstud

I have brown deposits on 3 of 8 cylinder head intake runners on a 6 month old engine. The other 5 are sparklingly clean. Keep in mind this is a throttle-body injected vehicle, so is that normal unevel fuel distribution; or is it indicative of some pathological condition? :D

The deposits weren't sludgy or anything, but marked and definitely obvious along the length of the runner against an otherwise new-looking set of trickflows. Also, all three runners appeared to have very similar amounts of sooting, with no particular order to the affected cylinders (they weren't all in the front, or on one side, etc).

:confused:

65Z01

Were they on the same side of the egnine?

Could the be realted to the EGR or cranck case ventillation system?

Ramanstud

not on the same side (well... two were, by default. :D ) As for EGR or PVC... unlikely. I suppose it's possible, but the affected runners weren't paired or clustered to coincide with the EGR dump in a crossfire manifold (the PVC is similar but on the other side of the intake manifold). That and I only have two injectors- which is why it disturbs me somewhat.

Could it be blow-by on valves or something? I got the heads assembled from trickflow, and I don't notice any other symptoms.

I'm switching to TPI as we speak (no EGR), so I may just wait and see.