Glow plug light - comes and goes...

[Kampingkris]

2006 Dodge Ram 5.9 - the glow plug light (coiled lines) comes on at weird times.. Sometimes goes away and doesn't come back.. sometimes it stays for 4-5 starts or so...
Truck starts okay. The last time it came on suddenly at 75mph... for no apparent reason.
The truck runs fine - with or without the light...
It's been checked out and they can't find anything serious - and of course - couldn't make it throw the light. No engine codes...

300,000 miles btw...
New injectors... aftermarket bullydog fuel system.... it really runs fine but this is getting old... and of course, we are traveling..

Suggestions?

 

[Tomcos]

Hello, I’m no help to ya because i have same problem but mine loses some power when it happens have you had any luck ?