if plugs and coils are good, it might be valve guides. mine (with around 50K miles) starting throwing misfire codes, and it ended up needing a valve job with new guides. have your shop do a leak-down test, which will isolate if this is it. if so, be prepared to spend > $2K or do it yourself (see my posting on DIY).

 

Finally, I will have some time this week to troubleshoot the engine light.

Before I start, my car is going to be 5 year old this June and its at 51xxx miles. Would this be still under warranty since it is a engine thing or dealer won't care for it?

tntrac

 

I believe everything is 3yrs/36K miles factory warranty on the S2000, unless you purchased an extended warranty like I did (no time limit/100K miles).

 

I thought engine/tranny are longer. But for my case, its really hard to point directly to whats at fault for?

 

I had this issue and it was a cracked exhaust valve. Do a compression check. If it fails on one cylinder (number 2 in this case) do a wet compression check. (cap full of oil into problem cylinder) and see if the problem resolves itself.

If it does not, upper half problem.

If it does than it is a lower half issue.

If none of the above; keep looking...

 

[QUOTE=racer_X_123,Feb 2 2011, 03:57 PM] (cap full of oil into problem cylinder) and see if the problem resolves itself.

If it does not, upper half problem.