98 c1500 atarting problem

hey guys im new to chevysand i swaped out a motor in a 98 c1500 with the 4.3L i got everything all dialed in and when I turn the key in the on position all the sensor and fuel pump turn on but when I go to turn the truck over theres nothing no starter click nothing. So i checked all the fuses relays and my wiring all of it is in the correct spot but when I was checking the number 8 fuse (crank) ground it out and the truck starts fine and purrs like a kitten. the security light stays on when i ground out the number 8 fuse any ideas on how to remedy this problem or if anyone can tell me what the problem could be? thanks jeff

probably security system is not allowing the fuel injectors to operate

in which is what the security system in these years disabled when there was a lack of code sent from the ign key switch to the ECM

if it is the kind without the chip in the key then you can try what i had to do to the 98 achieva we did with passlock no chip in the key security system

i cut the black/yellow wire coming out of the ign lock switch

snipped it, in the column

bene perfect ever since

after trying everything ot no avail

including: having the instrument cluster rebuilt twice

replacing the key switch twice

dealer three times

ended up not being repairable

very common issue with the late 90s security systems in GM vehicles

if the injectors are not firing when cranking then that is what's wrong


disable it


sometimes restting the security works for a little while

if the lighty is flashing then leave the ign key in the run position with dash lights on for about 15 minutes, or until the light stops flashing

then start it up

this resets the security