[41'srfun]

I've just replaced my injectors and intake manifold gasket on my 96' Vortec 350. It starts and runs fine, but with my hand held scanner hooked up when reading the live data the spark advance reads around -16 to -19 degrees and I cannot get it to read anywhere near the setting of 0 to -2 that it is supposed to be. If I advance the dist all the way to the right it will kick back when starting it like it is advanced too much, but when I back off of it so it will start like it should but it will not get close to the correct setting. I've had the dist. out several times and turned the oil pump shaft to try and get it closer to the right position but so far -16 to -19 at 1000 rpm is the closest I can come to getting it set. The truck has 166,000 miles on it and they are mostly highway miles. I've always kept everything well maintained and this is the first time that I've had any serious problem with it that I can't figure out.
Could it be the timing chain or maybe the camshaft position sensor? Or am I just looking at the wrong thing on my scanner? My scanner is an Equs 3140 and I am new to this sort of trouble shooting.
The engine runs fine , but the timing thing has got me worried that I may mess something else up on the engine if I drive it too much like that.

[BBCMudbogger]

If I'm not mistaken the 0-2 range is for the cam sensor value not spark advance. See if your scanner will show you the cam sensor value.Advance is controlled by the computer depending on load ect.