Archived my 05 won't start in cold weather

[hwtrucks]

I am having a problem with a 2005 Ram 2500 5. 9 when cold (below 50 degrees F. ) engine refuses to start. If you plug in block heater, engine will start even in the coldest weather. I have checked the intake heater and replaced the unit with a new one. All relays are working.

Thanks for your help.

 

[Missouri Mule]

I take it you saw no voltage drop when "wait to start light" stayed on? (The reason you replace grid heaters. )

The relays for grids are working correct?

Are you seeing voltage drop with new grid heaters?

Truck should fire up with out grid heaters at 50 degrees or lower. Are you using Biodiesel?



This symptoms when it appears on 2nd CTDs is usually a lift pump going bad I would recommend a fuel pressure test.