Hey y'all im new to the site but have been lookin through for some time now.
I have a 2008 dodge 4500 with a 6.7 around 240000mi on it. Changed the batteries in it a few months back, shortly after doin so the truck started to pulse all the time, not just when the grid heater is operating but all the time!!! This is frustrating its been to a dealer and a diesel mechanic a few times each and no one can figure it out tried the alternator had batteries checked replaced the fuse block, disconnected the grid heater and still nothing. Looks like i have an interceptor package installed for the lights...
Has anyone else come across this problem and if so what was done to fix this i really dont want to loose this truck to a dealer for a couple months

 

welcome to db have you tried to completely unhook the grid just to rule it out for sure i know you say it does it all the time but maybe it could be getting false readings from a failing sensor telling the grid to fire up. seen this happen on an early fuel injected truck. truck would run fine for about 5 mins. then wouldnt pull its self. it was 90 degrees out. temp sensor was telling the computer it was like -40 and it would start choking its self and run like crap. just something ez double to check

 

Thanks... is that the plug at the bottom of the intake? Also should i completely disconnect the solenoid for it....is the sensor part of the grid heater or is it external somewhere

 

it has a nut that holds the wire on if i remember right it is towards the cab from where the intake horn bolts . think its a 10mm wrench to pull the nut off

 

cool thanks...when i get into work tomorrow ill take another peak