# Cold start question



## Snipesy (Dec 7, 2015)

Definitely not normal at 20F, even with junk fuel. Youll want to get it fixed while you are under warranty (and definitely before you delete if you are doing that).

Have your dealer check the fuel pumps... make sure it builds adequate pressure when starting. If it doesn't, it's GM's policy to replace pretty much everything with fuel in its name.

They should also check the EGR... But thats something that should of thrown a CEL. Fair warning though, a clogged EGR is just a symptom to another problem. Don't let your dealer just clean the EGR and call it fixed.


----------



## IndyDiesel (May 24, 2015)

Snipesy said:


> Definitely not normal at 20F, even with junk fuel. Youll want to get it fixed while you are under warranty (and definitely before you delete if you are doing that).
> S
> Have your dealer check the fuel pumps... make sure it builds adequate pressure when starting. If it doesn't, it's GM's policy to replace pretty much everything with fuel in its name.
> 
> They should also check the EGR... But thats something that should of thrown a CEL. Fair warning though, a clogged EGR is just a symptom to another problem. Don't let your dealer just clean the EGR and call it fixed.


Agree with all you stated but the EGR. My EGR was dirty and caused a no start, that was about 41k, much of my driving on the first 25k Miles was in town driving, which is my theory in town driving clogs the EGR. At 55k miles now and almost all highway, I don’t expect it to clog soon. I had no CEL when I had no start with EGR. I cleaned the EGR, if had taken to dealer I think they would have replaced it. If I keep car for extended period of time, one of the biggest benefits to me with the delete would be blocking the EGR and preventing all of the crud being resent back into the intake. If I keep the emissions stuff, looks like to me the intake and everything may need removed and cleaned which doesn’t sound very appealing. Sort of sad to build an engine that could go 500k and due to emissions can’t make it to 200k without a lot of replacement of parts or cleaning stuff. I guess the positive is the engine can do it.


----------



## LiveTrash (May 24, 2015)

My glow plug indicator, no matter the temperature outside, will illuminate for a good 3-4 seconds and then I'll start it up. Try cycling the plug a few times (turn the key on, all the way off, back on, etc) then start the car and see if it makes a difference. Maybe the glow plug module isn't functioning as intended and therefore isn't heating up the plugs enough.


----------



## boraz (Aug 29, 2013)

LiveTrash said:


> My glow plug indicator, no matter the temperature outside, will illuminate for a good 3-4 seconds and then I'll start it up. Try cycling the plug a few times (turn the key on, all the way off, back on, etc) then start the car and see if it makes a difference. Maybe the glow plug module isn't functioning as intended and therefore isn't heating up the plugs enough.


i cant remember the last time ive seen the glow plug light on regardless of temp to -51


----------



## LiveTrash (May 24, 2015)

boraz said:


> i cant remember the last time ive seen the glow plug light on regardless of temp to -51


Really...? It'll come on every time for me. Even if I literally just shut the car off, it will come on. Mind you, if they're warm already from the car running it will shut off after half a second or so.


----------



## IndyDiesel (May 24, 2015)

Mine will come on every time cold, if engine is warm it doesn’t come on


----------



## nverges (Jan 28, 2018)

Thanks for all the advise. I shall update my post after I have them work on it again. Hopefully they will get to the bottom of the issue


----------



## justin13703 (May 2, 2016)

boraz said:


> i cant remember the last time ive seen the glow plug light on regardless of temp to -51


You must not be paying attention to it or the bulb is burned out lol. The glow plug light will come on even if it’s in the 60s outside. Positive 60s lol


----------



## snowwy66 (Nov 5, 2017)

I can't see the egr being the culprit. EGR has been around for over 50 years on the gasoline engine. I don't know when it was installed on the diesel engine. At least since 04. 

I"m thinking @*boraz* has a bad bulb. 

And sounds like @nverges has a bad glowplug relay or something to that effect.


----------



## boraz (Aug 29, 2013)

snowwy66 said:


> I can't see the egr being the culprit. EGR has been around for over 50 years on the gasoline engine. I don't know when it was installed on the diesel engine. At least since 04.
> 
> I"m thinking @*boraz* has a bad bulb.
> 
> .


clogged egr has stopped these cars from starting, thats proven....might not be this case, id lean bad fuel

my glowplug light does come on during startup when all the lights light up, so not a bulb

i always unlock the door with the fob pretty far away from the car....the car goes into pre start mode...cant remember if that includes glow plugs or not


----------



## justin13703 (May 2, 2016)

boraz said:


> clogged egr has stopped these cars from starting, thats proven....might not be this case, id lean bad fuel
> 
> my glowplug light does come on during startup when all the lights light up, so not a bulb
> 
> i always unlock the door with the fob pretty far away from the car....the car goes into pre start mode...cant remember if that includes glow plugs or not


No that pre start mode just by unlocking or opening a door doesn’t run the glow plugs. Remote starting will run them before cranking the engine, but yeah if it’s below like 70 degrees out and the engine is cold, that glow plug light should come on. 

But did you say the light comes on during startup when all the lights light up? That’s your glow plugs running. They will only come on in the time before cranking when your ignition is on. The light will not come on once the engine is running or with the key in any other position than ignition. Also once it runs a cycle, if the engine isn’t started it won’t run another cycle until the key is turned to off, then back to ignition again.


----------



## snowwy66 (Nov 5, 2017)

justin13703 said:


> No that pre start mode just by unlocking or opening a door doesn’t run the glow plugs. Remote starting will run them before cranking the engine, but yeah if it’s below like 70 degrees out and the engine is cold, that glow plug light should come on.
> 
> But did you say the light comes on during startup when all the lights light up? That’s your glow plugs running. They will only come on in the time before cranking when your ignition is on. The light will not come on once the engine is running or with the key in any other position than ignition. Also once it runs a cycle, if the engine isn’t started it won’t run another cycle until the key is turned to off, then back to ignition again.


He said he couldn't remember the last time his light came on. Even down to -51 degrees.


----------



## justin13703 (May 2, 2016)

snowwy66 said:


> He said he couldn't remember the last time his light came on. Even down to -51 degrees.


Look in his post right above mine. Second paragraph.


----------



## snowwy66 (Nov 5, 2017)

justin13703 said:


> Look in his post right above mine. Second paragraph.


Look at his post on page 1. Post #5.


----------



## boraz (Aug 29, 2013)

justin13703 said:


> No that pre start mode just by unlocking or opening a door doesn’t run the glow plugs. Remote starting will run them before cranking the engine, but yeah if it’s below like 70 degrees out and the engine is cold, that glow plug light should come on.
> 
> But did you say the light comes on during startup when all the lights light up? That’s your glow plugs running. They will only come on in the time before cranking when your ignition is on. The light will not come on once the engine is running or with the key in any other position than ignition. Also once it runs a cycle, if the engine isn’t started it won’t run another cycle until the key is turned to off, then back to ignition again.


so does my glow plug light come on with all the other lights when its 100f?


----------



## Rivergoer (Mar 30, 2017)

boraz said:


> so does my glow plug light come on with all the other lights when its 100f?


Here in Arizona over 100F we do get a glow plug light for a few seconds after switching key to on prior to cranking the engine. I always let the glow plug light cycle to off before cranking.


----------



## justin13703 (May 2, 2016)

boraz said:


> so does my glow plug light come on with all the other lights when its 100f?


I don’t really know what your car does but yeah it probably would run at 100. The glow plug light being on when you turn the ignition on isn’t a “check” kind of thing. If that light is on, your glow plugs are on


----------

