1998 gmc savana 1500 5.7 blows ecm fuse as soon as key is put in the vehicle

was running hit a pothole and died would not start the ecm1 fuse was blown i replaced fuse faulty oil pressure switch fired right up until died minutes after now fuse blow when you put key in please help

Start checking for wires grounding on the body or frame. Wiggling the harness will also help find the short.

Check the main wire harness near the left upper control arm, wires are known to break or rub near the frame.

i have not found any loose wires i have been checking.. any other ideas ?

all it can be is the wire touching ground some where either at the plug or rubbing the chassis. or there is an internal short on one of the things on that circuit, which is possible but infrequent. you could tell by simply unplugging them if one of the things you unplug stops the fuse from blowing thats your fault