While replacing the timing belt I put a dial indicator in the sparkplug hole. My crank gear has marks on two adjacent teeth. The first tooth is .220 piston travel before TDC and the second is .110 before TDC. I have been told the corrcect mark is the valley between the two teeth. Are the marks this inaccurate? True TDC is the valley before the valley between the two marked teeth. Should I use my indicator as TDC or us the valley that is .110 piston travel advanced? Or is one of the marked teeth the timing mark I should be using. My two manuals just say line up the timing marks.