I tried to set the timing on my 89 lo5, i disconnected the brown wire by the heater box and checked the timing. The problem is the mark does not even come into view.

I tried switching to the number two cylinder just to see if i could see the mark and it showed up, way below the timing indicator.

so i'm wondering if im doing something wrong, or if the balancer has slipped.

 

Sounds like your balancer is farkled....

2 is supposed to fire 90° of crank rotation before #1. So if #1 was set to fire at exactly TDC (0°), and the timing mark should show up at 12:30 at that instant, then #2 firing should be at about 9:30.

Put your timing back where it was, wherever that was, and get a new balancer, and then try again.

 

If you want a quick-and-dirty check of your balancer condition, observe the timing groove in the outer ring in relation to the keyway in the hub (you'll need to remove the crank center bolt to see the keyway). The timing groove should be retarded about 7° from the position of the crankshaft snout keyway. If it isn't, your elastomer is probably failing and allowing the outer ring to slip, as well as not dampening harmonic vibrations as well as it should. Reinstall the crank center bolt to 65 ft/lb and go shopping.

 

It was my impression that in order to set base timming on our cars you have to disconnect the 4 wire harness that comes out from the bottom of the dist., I have never heard of disconnecting the "brown" wire. maybe it changed over the years but I know up to '86 they were the same.

 

Earlier TBI and CCC engines had the flat, four-wire connector that was disconnected to bypass the EST. Later TPI engines were equipped with a single wire connector to bypass the EST system, and I believe the TBI systems had the same single connector.