1999 Tahoe 5.7L-No Security light = No start issue- SOLVED

[squid48072]

99 tahoe -Any one come across this issue - when key is inserted I am not showing a security light notification which is causing a no start (Cranks but no start) I tried a new ignition lock cylinder with no luck. I disconnect battery for a day and reconnected and was able to get a security light and was able to get it started on first turn. However, once I shut it off it wouldn't start again-same issue of no security light. Before I take this to auto shop thought I would check if anyone had any solution to this issue.

 

[strutaeng]

Ummm. Why don't you start with the basics:

1. Do you have spark when cranking? Check a few plugs...

2. What is your fuel pressure? Does it hold pressure?

3. The "spider injectors" fuel system is infamous for all kinds of issues, from FPR leaking (you really can't see this because it's all hidden inside the upper plenum of the intake), to injectors hanging open when hot, flooding the cylinder(s) leading to causing a crank-no-fire condition when hot. Or injectors just plain die.

4. Distributers and/or ignition control module (ICM) are another common problem areas in those engines. Cap and rotors are common problems too. Aftermarket cap and rotors seem to last as little as a few thousand miles before corroding away, especially in damp climates.

 

[squid48072]

Thanks it has all new fuel pump, fuel filter, spider injectors and fuel pressure regulator and distributor all within the last year. I have not replaced the ignition control module.

 

[Eman85]

Best solution if it truly is a security system issue is to bring the PCM to someone that can reprogram it and eliminate the security feature. The only people the security feature has ever stopped from starting these vehicles is the owner.
Resetting of the security requires key on and leave it like that for a period of time, you'll have to google the info as I forget more than I remember now.

 

[squid48072]

ignition control module looked like original so I replaced but still no security light and no start. Its off to shop to figure this one out.

 

[GMCChevy]

Usually if it's a security issue there's a no crank or a light.

 

[exp500]

RTFM -
Free Service Manuals for GMC vehicles | Operation CHARM

 

[Eman85]

When I had a security issue it would crank and attempt to start and the PCM shuts the injection circuit. You could repeatedly attempt to start and get the same results.

 

[squid48072]

Solved - It need a new ignition switch

 

[ZEUS1]

Does replacing the ignition switch always solve the security issue? i ask because i just replaced a spider, and now i have the same crank, sputter, and no start issue.

 

[Eman85]

Does replacing the ignition switch always solve the security issue? i ask because i just replaced a spider, and now i have the same crank, sputter, and no start issue.

No OP had a no security light problem so I'd say the PCM wasn't getting powered up correctly which is why no security light at all.