r/suburban

I’m having some trouble with my 1998 GMC suburban 1500 and I think it may be some sort of computer issue. Or a grounding issue
Possibly I believe it is the passlock II security feature in the car, the symptoms are as follows

Car will crank and start up just fine for about 1- 1.5 seconds then die or stall out, giving it gas with pedal merits zero change

When this happens, before I even turn the key to start position and it is in only the ON position I notice that the background lighting for the gauges doesn’t come on, when it usually does, and my interior lights don’t come on when they usually are able to when truck is starting normally. Also the door open alarm or “beep”does not sound when the truck is doing the no start thing

I have replaced the entire ignition switch and harness with brand new myself and it didn’t solve

This started during the hash winter we had this year in Ohio, towed the car to a heated garage where it sat for a few days and then it magically had the issue solved, now it is happening again, for a while I could get the car to work by turning the key past “ON” position but not quite enough to turn the engine over and firmly bumping the top of the steering column with my palm, seemed to jostle it into working as well as the back glow for the gauges and everything coming back to life however this isn’t working now. Also sometimes if I leave the key turned to the “ON” position for 5ish minutes it just randomly clicks all the gauge lights on and it then starts just fine. Another weird thing is the green “headlights on” indicator is turned on when it DOESNT start but goes off when the back glow for gauges starts working again, the headlights in this car are always on for some reason day or night, they too will not come on along with the gauges back glow and then will pop on when the car is going to start like normal, this is how I usually tell wether it’s going to start or not.

The reason I think it’s the passlock II feature is it seems to be turning the injectors off after I start the car. But this doesn’t explain why the car will start when the gauge lights and interior lights are working , and when they aren’t working the car won’t start
I have tried the 10 minute 3 times relearn process, disconnecting battery and reconnecting
Hooked up to a scanner and zero codes pop
I have three different keys for this truck and none make a difference
Also it is a brand new battery
I checked the grounds by firewall under the hood
Tried to check the ground under the steering column and they everything looks okay to me, though I will say while I’m very mechanically inclined as soon as it comes to harnesses and wiring I loose any ability, grounds don’t seem to have any corrosion or anything
This is a Wyoming origin car and has been in Ohio for about 1.5 years, so zero body or frame rust/corrosion. I drove it here 24 hours straight with my grandpa after he gifted it to me so it is very sentimental to me.
This is my first Reddit post ever so sorry if it’s too long I am hoping some of you guys have some ideas

Let me know if you have any ideas or need more information or need a video or photo or something, thank you for taking the time to read

Anyone have any suggestions for aftermarket tow mirrors? I purchased some from Amazon with decent reviews but they're not working out. I have a 99 suburban

The little strip of led lights (running lights) went out on my passenger side headlights a few months ago. Now the turn signal is not working. I can see a lot of moisture inside the headlight assembly. What are my options? Am I screwed (I am thinking a new assembly plus instill isn’t cheap).

In my old 2005, I could very easily just get a new bulb from autozone and install myself.