Ive got a 94 s10 blazer 4x4, 4.3 and 5 speed. had it for a couple weeks and just after getting it i replaced intake gaskets and valve cover gaskets. i also replaced the coolant temp sensor (to guage) has had cap rotor plugs and wires replaces this year. theres a receipt for the parts in the glove box from napa and they look new...
heres the problems, i am pretty sure the balancer ring spun so setting time with a light is not possible. when i put distributor in i got cyl 1 to tdc on compression stroke (made sure valves were closed while valve cover was off, and had piston as far up as it would go) Ive also got a big idle issue, when im driving it, it seems fine, no missing or surging and seems to have power throughout. at idle its missing and carrying on like it wants to die, but never does.
for the time being i have map sensor unplugged because it runs much much better with it unplugged in limp mode. i have checked for proper operation and cleaned, egr, iac, tps, coolant sensor (to ecm). checked for vaccum leaks to the point of completely disconnecting lines for ac controls, since there not easily accessible...
i know there are a rack of people who have had this issue, but cant see where they fixed it.(google, other forums, here) im not likely going to just start replacing things... but if youve dealt with this please please let me know what you found.
thanks.

 

Anyone think a tho kit would help? Just thinkin maybe putting to much fuel in at idle?? And there is 240k on the clock so it can't hurt, just wondering if anyone thinks it may fix it??

 

Throttle body rebuild kit is what I'm curious about.... Don't know what happened before...

 

Do you have CPI or TBI? Im also having same prblem with harmonic ballancer. My timming marks are way off and cant set with timming even after unpluging wire under pass floorboard. Maybe my harmonic ballancer spun also. The timming mark on it does not match up with the keyway

 

Mines tbi. I haven't physically checked the marks in relation to keyway. But they sure don't seem to be at tdc

 

Well checked balancer today, totally spun.. guess I need to get one... Gonna check vacuum and fuel pressure tomorrow to see where I'm at there...

 

Well fuel pressure and vacuum checked okay. Vacuum is around 20 or so.. fuel pressure where it is right around 15. When I went wot, it moved to about 12-13ish then right back to 15 or so. Found the muffler to be leaking around each end right at the bead, and it looks like a bomb went off inside it. It apears to have expanded somehow.. that or a gremlin got inside with a sledge and beat it from the inside out..
So i guess on payday in gonna get a balancer, muffler and ac delete pulley and hope with proper exhaust flow and timing shell be at least closer to right....

 

Well got balancer pulley and muffler on. Idled a lot better being at 0 degrees tdc helped a lot. Now my issue is that of I go to wot, it falls on its face for a second or two then pics up. Driving on interstate seems fine. But at lower rpms, or idle if I punch it has that hesitation.

 

Anyone have any ideas??