I sent you the circuit for the injector between them and the ecm for your review , it is a link to my dropbox so you can downloaded and zoom in on it
2 wires , b+ from main relay and ecm control on the other
Most common cause
1- ground loose , check all ground from engine block to frame .
2- injector wiring from main relay( i sent you a picture location for it ) or from ecm control wire
3- injector themselves
4- Check the spark plugs & coils ,have they been changed, have you checked ?
5- defective ecm
Let me know if you need anything else on it , just reply back here & we can continue.
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