hello my name is glenn i am working on a94 s10 blazer 4.3L cpi vortec 212,000miles . i have 9145actron scan tool when you check the time advs. it randon # 0-27 flashing in other words you can,t tell what the timing is or the advance . i have not put a timing lite on it i guess that next thing . it obd 1 it had code 34 and 45 . any in put would help thanks. glennt     ps the motor is missing but once you have get some rpm the miss leaves and truck run ok but it is dumping to much gas. plugs sutted black #1cyl 125 lbs .compression also the scantool say the 4x4 is in gaged and this is a 4x2 .the truck has been tacken care of the guy that owner love his truck thank again glenn

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1994 Chevrolet s10 blazer 4.3L cpi vortec

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alot need imput some more gray hairs thinking