Well, I tried to adjust my valve clearence today and probably messed something up. When I put everything back together valvetrain was noisy and check engine light came on. So, I'll go to the shop tomorrow to fix it. Can check engine light come on if valve clearence is wrong? I'm afraind if I messed up something else. Also, Is it important for the engine to be in TDC when doing the valve job? I tried to get it into TDC, may be I was off a little.