The offical diagnosis from American Honda is an "oil control ring failure". (I have no clue what that is.) This caused the check engine light to go on, and only 90psi of pressure in #4 cylinder. When they took the thing apart they found abnormal markings on the cylinder wall.This happened on an 05 w/ 6k mi. According to them "they have never seen this". However given the number of posts on check engine lights and #4 cylinder problems you gotta wonder.
I'm still debating spending money for a new 06 vs repaired 05 vs different product.

 

If this is going to be a street car, I'd take the offer for the free extended warranty. If it's going to be a track car, the warranty will probably not be of much value, since they will claim "abuse" if you try to use it.

 

Get the 05 fixed, dump it, then buy another one. It's just money. If you feel better with the 06, get the 06. See what the dealer will give you for it. They know it has a new motor. I'm sure they'd be happy to sell you an 06.

If you're not watching the oil level closely though, the 06 could easily have the same problem as the 05.

 

It doesn't make sense that only cylinder #4 would have Oil problems compared to the other cylinders.

My motor blew last week. Stock motor and I've NEVER had a problem. I did my oil changes as usual and out of no where "click click click knock knock knock"

Cylinder #4 took out the spark plug and destroyed itself. I think it could be a bad injector or a design flaw in the intake manifold.

I have yet to hear if Honda will warranty the repair.

I love my car too much to trader her in but I'll think twice before reving it into VTEC

 

Why not? It's the farthest away from the oil pump.

Anyway, the facts are that #4 has historically had almost all of the oil starvation issues. Search this site yourself if you don't believe me.

 

hmm, you would think with a motor that revs to 9k we wouldn't have a problem generating oil pressure

I thought the RSX guys use the f20c oil pump as an upgrade.

Maybe it's time the aftermarket came up with an oil pump for the S2000

 

It's not the pump that's the problem, it's the pickup. If you are low on oil, or if you are in a sustained high-g sweeper, you can run the pump dry or nearly dry. As the oil pressure falls, the cyl that will be affected first is the one farthest away from the pump -- usually.

 

So a baffled oil pan seems to be the best solution