3520 cold start

[svlsmokey]

2015 3520h with 570 hrs doesn’t like the cold any more. Before about a year ago it started like a champ every time even in the coldest weather (0-10 degrees). Now if it’s not plugged in, it will turn over and over and over but rarely start. Is there some kind of relay or control module for the glow plugs? Or maybe it needs new glow plugs…. Ideas? I don’t mind plugging it in for real cold weather, but for 45-50 degrees it’s a bit much.

 

[ptsg]

There is a module that controls the time that the glow plugs are On based on coolant temp. However, I would check the fuses first, then check if the glow plugs are actually getting power and if they're actually working.

 

[52wej]

Check your glow plugs. I had the same thing happen and it was the plugs. W. Jones

 

[North to Alaska]

Check your battery? old batteries can turn over but not fast enough to get it started. The cold will cause a large drop in amps in the battery. Also, a good battery will lose much of it’s power if left to sit many days in real cold temps with out getting used and recharged.
Other cause is older/sheared oil will lose its “fluidity” in the cold temps. A good 0w40 will do wonders for starting in very cold temps.

 

[Slowpoke Slim]

My bet would be glow plug related issue.

No way that shouldn't fire right up at 0F if it's plugged in.

Unless your starter is cranking *very* slowly.

May want to switch to a synthetic engine oil also.

 

[FastEddieR]

Are you using a winter blend diesel? Or did you put anti-gel in it? Rule out slow moving fuel along with faulty glow plugs and/or weak battery