Hey, I own a 1991 Blazer 4WD and love to get it full of mud. I'm also a mechanic but I am stumped on a 1994 GMC Jimmy that my brother in law owns..., I need some advice! Ok, the engine was replaced several months back and has been doing fine. Recently the idle would become erratic and transmission would start shifting funny when check engine light came on. He removed the ecm 1 fuse and would replace it and everything would be fine. The other night the vehicle cut off while going down the road and lost power to most of the fuses. Check engine light no longer comes on with turn of the key. No fire, fuel, but spins over. No power to one ecm fuse, the ecm b fuse does have power. Little confused...., any ideas????

 

for starters, it sounds like you need to be posting in the right tech section, not the Build thread section.

it sounds like you had a fuseable link fail for the sudden loss of power throughout the fuse panel. could also be a broken power wire connected to the alternator.

you mention having SES codes come up.....did either of you guys bother to scan it for the codes? that will go really far in determining what may be wrong with the erratic idle & trany problem.