Hello. I recently (within the last 2 months) bought a 2004 Silverado LB7 that needed new injectors. I have since replaced the injectors and the truck runs ok now. My problem is I now have a security light on in the dash and the serial number is corrupted. Not only that, I cannot read the ECU with EFILive to even flash the computer. I'm not sure the security light was on when I bought the truck but I'm sure it is now. The truck sat for almost two years before I got it and I know it sat for at least two weeks with no batteries connected.

I have tried using my V2 to cal flash the ECU but it says the computer is locked with a custom key. It tried over 3200 something keys and it took several hours.

Also it seems to lose it's prime when it sits overnight. I seem to have to prime the fuel before I start it or it cranks a long time before it will start. But if I prime it it will start quickly and after it runs a few minutes it will fire off immediately when I try to start it after short period shut downs.

My main concern is the security light. I need to get that sorted first.

Any suggestions?