ABS rotar gap

Hi
does anybody know what the effective puck up gap should be between the front ABS sensor and the rotar ring ?
Also can the ring be dressed as there is corrosive pitting on mine
If the ring has grease on it with this effect the ABS pick up efficiency
13a VVT 2005

I set mine by eye, if the gap is too big it will show a fault - mine did. I did use a bit of emery cloth to clean up the ring but only a little. Also the little plastic spacers which fit around the abs sensor were shot to pieces on mime so it went back together without them, had no problems without them.

thanks KJS
yes I ran the dremmel round the ring anyway and supper cleaned it and the fault has gone away
i did a resistance check on the sensor and that showed not an issue so it must have been the ring
funny but you don't see rings for sale but mine has a bit of corrosion
I did get the plastic sleeves back in ( in two half's) but am surprised that in your case the appear not to effect the system
just goes to show Eh
thanks again for the help I was trying to find out of the ring had reduced through corrosion really but as I said its light out just now so good result
keep on posting