so my blazer has a lot of hesitation when under a heavy load like going up a mountain from a slow speed and I used my scan tool to look at live data and noticed my ignition advance readings was showing -15 degress at idle and when giving it wot in park seen it spike to -12 degress shouldn't this be at 0 at idle and advance when giving it throttle? mine is the older style cpi with metal plenum but has the flat side post distributor and don't know if I can just loosen the mounting bolt some and rotate it counter clock wise to advance it to 0 at idle?

 

I have had a cam retard timing indicator permanently -8 degrees, no matter of RPMs. I had to advance one tooth in clockwise direction to bring it exactly at zero. Give it a try, You can always set it back if it won't help.

 

i don't think it is off a whole tooth tho if it was it would be worse than this wouldn't it I was hoping I could just loosen the mounting bolt some and rotate the distributor enough to make it 0 or close to 0

 

No, you want you're ignition advanced at idle. Old school cars with points dist would run 10° btdc, and the vacuum advance would increase even more. The vacuum advance would drop out when the throttle was opened wide.

The more before top dead center it is, the more its advanced. So the more negative the number goes, it's advancing

 

Seems logic. On second thought I probably didn't try rev up the engine with a check engine on.

@OP Anyhow, in my case one tooth advance was equal to 8 degrees on idle. I can't imagine You shift half of the tooth. IDK what type Your distributor is, but usually they lock in a one fixed position by the bolt to the LIM block. The mechanical correction can be done by (de)advancing coupling of the distributor shaft to the oil pump.

 

mine is the flat distributor i guess 95 was the 1st year for that style. yeah at idle my timing advance is -15 and giving throttle wot for a split second it goes to -13 and i think that is why this thing struggles on high loads like going up a mountain around sharp curves it just has no power at all till you get to about 3000 rpm then it has some power but only on high loads. if it is a straight flat road it has plenty of power just only on high load on the motor is when it has no power

 

So, the timing is not adjustable on the horizontal distributor. And I'm not really sure the timing is causing your issue. 15° BTDC seems pretty much spot on for idle. Your problem is a lack of power under a heavy load? Have you checked your fuel pressure?

 

fuel pressure is good has new fuel pump and new filter in it. just did another data scan on my scanner while driving timing advance is -15 through -19 at wot and -20 through -26 at idle now it changed since last time i did the scan. long term fuel trim at wot is 1%

 

Timing will change depending on load, etc. Those numbers seem fine to me, though

What were the fuel pressure numbers, and did it leak down any?

 

60 psi stayed at 50 when off. it might be a torque converter issue maybe it is worn out because sometimes it has a lot of power and pulls hard and fast when passing someone and sometimes when you pass someone it is sluggish and slowly pulls but sometimes it pulls like it has a v8 in it and gets to 75 mph in a few seconds lol