My truck was a 2003 Reg Cab Silverado with manual accessories and 4.3L V6. I did a complete swap to all power accessories and 5.3L V8 including all the fuse boxes, PCM + BCM, interior and engine wiring off 2003 Reg Cab also.

Everything is connected right and nothing seems damaged. The first try, I turned the key and the security light came on. I did the relearn thing and the security light went away on the 3rd try but on the 4th try it still didn't start. I tried the relearn thing 3 differnt times.

The crank turns over and you can hear the fuel pump working. I removed the #1 spark plug wire and stuck a spark plug in it to see if there was spark, but no spark.

I need help please.

 

How were you testing for spark? Did you ground the electrode by touching it to something metal or just hold the plug up in the air?

Check your coil pack connections too - I forgot to plug one of mine in when I first swapped in my 6.0. It ran on 4 cylinders but it felt like ****, I thought it was a serious problem.

 

Yeah I just held the spark plug in the air. I went thru every single connection and ground wire in the truck and they were all connected right and tite.

I have an OBD-2.com scanner I hooked it up to and there were no codes.

 

Can I just bypass the factory alarm or VATS (if thats the problem) and see if that works?

 

You need to ground the electrode to a good clean metal engine part to test for spark. If you don't do that there's nowhere for the current to go. Try it again, touching the electrode end of the spark plug to a good ground and see if you have spark. If the truck turns over but won't start it's either spark or fuel. You may need to have a crank angle sensor (CASE) relearn done too.

 

I think the truck is not getting fuel due to the VATS and may have messed up my fuel pump but the truck still wont turn on

 

Hmmm....I'm not aware of a way to bypass it.

 

If the VATS was causing it to not start (it does crank), would there still be some fuel in the fuel rails? I pushed the shrader valve on the fuel rails and fuel did squirt out.

This was before and after the Passkey 2 "30min" re-learn proceedure.

 

I'm not 100% sure how VATS works, but I think it's an ignition kill, not a fuel pump kill. If you are getting fuel squirting out the schrader valve then you are getting fuel pressure. Sounds like you're not getting spark. I also thought that VATS would allow the truck to start and run for a few seconds then die, but I might be incorrect about that. When it tries to start does it sound like it might catch? Or does it just sound like it's cranking and nothing is happening at all?

 

Here are some threads to check out. If you didn't follow the relearn procedure exactly it won't work

https://www.performancetrucks.net/fo...highlight=vats
https://www.performancetrucks.net/fo...curity+relearn
https://www.performancetrucks.net/fo...curity+relearn

Make sure doors are all shut and accessories are all off. May want to hook up a trickle charger too, as it may take some time to do.

PROCEDURE:

1.Insert key, attempt to start the vehicle and leave the key in the ON position.
In some vehicles, the Battery and Security light will blink for several seconds, and then shut off. Then the Security light will then remain ON. Leave the ignition ON until the Security light goes OFF. This will take more than 5 mins.

2.When the Security light goes OFF, turn the ignition to the OFF position.
Leave ignition OFF for 20 Seconds.

3.Attempt to start the vehicle again and leave the key in the ON position.
In some vehicles, the Battery and Security light will blink for several seconds, and then shut off. Then the Security light will then remain ON. Leave the ignition ON until the Security light goes OFF. This will take more than 5 mins.

4.Turn the ignition to the OFF position for 20 Seconds.

5.Attempt to start the vehicle again and leave the key in the ON position.
In some vehicles, the Battery and Security light will blink for several seconds, and then shut off. Then the Security light will then remain ON. Leave the ignition ON until the Security light goes OFF. This will take more than 5 mins.

6.Once this entire procedure has been completed (three times) your vehicle will start on the fourth attempt.