94 seirra service engine soon light
 

Hell everone hope someone can help I put new head gasket on my 4.3 v6 after puting everthink back the ligth come on has anyone had this problem plz let me no anythink what to ck will be a big help

You need to read the code......94 is OBD1, code readers are cheap for them....some people use a paper clip to short across 2 contacts to do it.

Attachment 1699

I hav the code it's 42

42 Ignition control module (ICM) – electronic spark timing (EST)/ignition control (IC)/bypass circuit malfunction Wiring open circuit/short circuit to ground, ICM, ECM


The rest of the codes can be found here for future reference

GM 92-95 C/K Pickup OBD Trouble Codes ?