Setting Timing 98 Sierra

[shoultsc]

I am wanting to set the timing on a 98 sierra using ot-2 scantool. It gives me the Timing Advance which displays around 20 under 1000 rpms and increases with the rpms from there. Everything I have read says under 1000 rpms should be around 0 and over 1000 rpms should be withing +-2.

Need help understanding the timing advance with the ot-2 and how to check the timing with it.
Thx,
James

 

[98trck]

My '98 350 auto 2wd was crank triggered ignition i don't think it is adjustable make sure your distibuter is phased correctly my truck had a miss when i replaced the cap and rotor i noticed the burn mark on the rotor was at one end i rotated the distributer and no more miss
what engine and trans do you have 2wd or 4wd