2014 sierra deleted 5.3 immediate stall on start up

[duffy]

Do you have a scan tool that will allow you to graph the O2 sensors?
That might be the easiest way to determine which sensor is giving odd data.

Also, if the new sensor can be swapped from Bank 1 to Bank 2, that might allow you to see how things behave that way.

I’m not sure if it will do that or not but i will see what all it can do.If not i will get one of the boys i know to plug in.That’s a good idea to switch sides.I seen something online about the upstream can act up but show as downstream also.I’ll try the swap and if it doesn’t work i think i’ll get someone to plug in do some testing for me cause i could throw sensors at this thing all day.Thanks

 

[Bladecutter]

I have to ask, since I didn't see it listed, but have you checked the coolant temperature sensor and the air temperature sensors to see if they are valid? That's something that can throw off starting performance, if it trying to add too much or too little fuel on a restart.

 

[duffy]

I have to ask, since I didn't see it listed, but have you checked the coolant temperature sensor and the air temperature sensors to see if they are valid? That's something that can throw off starting performance, if it trying to add too much or too little fuel on a restart.

No i haven’t.I have noticed if you start the truck and drive say a km and the coolant temp just starts to move and you shut it off it will start perfect when you come back out.If the engine is at operating temp and you shut it off and immediately start it back up it will start but stumble a little but give it 5-10 minutes and it’s start like crap time.That’s why i wondered about the crank sensor thinking it got hotter after it was shut off.Looks like i need someone with a better tool than i have to check these other sensors.Can these be tested with a good tool or do i need to do an ohm test or something.Whatever is going on seems to be temp oriented because once it’s at full temp going down the road you can tell either fuel or fire is not quite right and it’s not running smooth like it was.Just a slight change in engine smoothness.