I have an 03 monte with a 3.4L in it. I am having issues with it starting. I crank it over and it has fuel but no spark. When i turn the key on the security light comes on in message center and does not allow the car to start. I have read on other sites and forums that the passlock system is not working. I have tried replacing the ignition switch and the ignition lock cylinder neither of these have fixed the problem. I tried the reset process with the key in the on position till the light goes out after 10 -11 minutes but it does not go out. I do not know what else to look into. Any help would be greatly appreciated thank you.

 

Since you have an active Security message, this definitely sounds security related. But I believe it stops the car from cranking (either that or it stops the injectors from firing or both). How do you know for certain its not spark?? Did you used an inline spark tester?

Since you replaced the lock cylinder, which has the Passlock chip on it, then you definitely need to do a security relearn. You cannot get around that. I know there are different instructions floating around and they are a little different. Attached are the instructions as found in the GM shop manual. You MUST follow the instructions to the letter until the car finally starts. Small tip, before putting the key in, activate the e-brake. By doing so, it will prevent the day time running lights from draining your battery. A common mistake, people will remove the key. Do NOT remove the key. Once you put the key in, leave it, never remove it.

I hope this helps you.

 

I did this and it seemed to work for a bit and now I am getting a crankshaft position sensor code. It will go back to not starting or starting and dying right away then starting and running just find the second crank. Going to throw in a crank sensor and see if that does it. Otherwise I have no idea what to do.

 

A bad CPS can most certainly prevent starting. They are not that expensive, but replacing them can be a bit challenging on certain engines and vehicles. (I replaced one not long ago on a 3.1l V6)

 

Thanks for the help guys the crank sensor fixed it. Starting perfect now.