Chevrolet Repair Questions? Ask a Chevy Mechanic for Answers ASAP
That was a robot, just ignore it now.
Check the fuses for the ecm/pcm. One second and I'll tell you exactly which to check.
I don't see a 5.3 listed for the 1999 Sierra, can you give me your vin?
No wait, I found it. Check these 2 fuses, the ECM1 and ECMB, both in the underhood fuse block.
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