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Smell of burned plastic on start

rauan

rauan

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Does anyone experience the sane thing? Very often when I start the truck I can feel burned plastic smell inside the truck.

I have 2500 with Cummin engine. I heard it has auxiliary heating system and I was wondering if that could be a reason.


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I wouldn't worry about it. Mine smelled a bit for the first few hundred miles. I have a 3500 with the 6.7l HO. The "aux heating system" is actually a cooling line that passes from the turbo into the heater core. The exhaust from the engine heats up that coolant and it is passed into the passenger compartment. There is no "electric" heating element aside from the intake heater. Let the newness burn off... Its all good.
 
flan said:
The hvac system does in fact have an auxiliary supplemental cabin heater as standard with the Cummins engine option, regardless of trim and it is electric.
Click to expand...
Not going to get into a pee pee contest with you but not so…. The engine will actually idle up to increase the exhaust temp. The coolant passed through the turbo and goes to the heater core. It works better when the engine brake is on full…. But, hey I have been wrong before. Now your intake heater may click on and off when it’s really cold and that could give you the impression of an electric heating element for the cab.
 
js4024 said:
Not going to get into a pee pee contest with you but not so…. The engine will actually idle up to increase the exhaust temp. The coolant passed through the turbo and goes to the heater core. It works better when the engine brake is on full…. But, hey I have been wrong before. Now your intake heater may click on and off when it’s really cold and that could give you the impression of an electric heating element for the cab.
Click to expand...
From the FCA workshop manual:

The heater is located in the heater box downstream of the heater core. It consists of three 400W resistors, which translates to 100 amps at 12 volts.

Operation is automatic, based upon the following conditions being met:
-Engine must be running at 700RPM or greater
-Outside temp is below 68F
-Coolant temp is below 158F
-Battery voltage must not fall below 12.6

This supplemental heater can be had on vehicles with automatic or manual climate controls. Check your fuses / relays under the hood. The manual calls it a "Positive Temperature Coefficient" heater, or PTC.
 
js4024 said:
Still call bull poop, mine starts cold and stays cold until the temp gauge starts moving. But hey, I’ll just say you are right….
Click to expand...
Perhaps if I give you the part number to look up?

68396041AA

All those parts sites can be wrong like me? Idk....
 
js4024 said:
I wouldn't worry about it. Mine smelled a bit for the first few hundred miles. I have a 3500 with the 6.7l HO. The "aux heating system" is actually a cooling line that passes from the turbo into the heater core. The exhaust from the engine heats up that coolant and it is passed into the passenger compartment. There is no "electric" heating element aside from the intake heater. Let the newness burn off... Its all good.
Click to expand...

My truck is relatively new as I received it from dealership on December 1st, but I already have over 5000 miles on it.


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flan said:
The hvac system does in fact have an auxiliary supplemental cabin heater as standard with the Cummins engine option, regardless of trim and it is electric.
Click to expand...

I also heard it has auxiliary electric heater.


Sent from my iPhone using Tapatalk
 
js4024 said:
Not going to get into a pee pee contest with you but not so…. The engine will actually idle up to increase the exhaust temp. The coolant passed through the turbo and goes to the heater core. It works better when the engine brake is on full…. But, hey I have been wrong before. Now your intake heater may click on and off when it’s really cold and that could give you the impression of an electric heating element for the cab.
Click to expand...
Here’s the schematic for the PTC Cabin Heat system- https://drive.google.com/file/d/1SQ4iuLlafSXy_Gq4Nqns4UzHcuWr0448/view?usp=drivesdk
Here’s the location of the heating element in the hvac box-
20CB1CD1-892E-4774-9CC1-D30EE3D5CB57.jpeg
That aux fuse box towards the back of the engine bay on the driver side houses it’s three relays and j-case fuses.
 
I have smelled the same smell also. I cant say for certain what the source is, however I attributed the smell to a combination of:

1. All new interior components (plastics) in the cab being exposed to heat in the first few weeks of it being new.
2. The heated seat and steering wheel components getting hot (the steering wheel heater can really cook when it first starts up!)
3. The auxiliary electric cabin heater element kicking on for the first few cycles as it warms the air in the HVAC system

I have close to 3,000 miles on the truck now and that smell is less apparent / common than it was in the first few weeks.
 
js4024 said:
Still call bull poop, mine starts cold and stays cold until the temp gauge starts moving. But hey, I’ll just say you are right….
Click to expand...
Look at your aux PDC and you will see all the fuses for the electric heater….


To the OP i had the same smell for about 6-8 months when i was on low heat it has gone away i would not be concerned
 
Smell started once it got "really" cold. That was when the truck had around 7k miles and it was probably around October/ November here in the midwest. Before when the ambient was >40F I never smelled anything. Maybe it is the Intake air heater or the coolant aux heater? I also had my intake air heater relay checked by the dealer as part of a recall and everything was ok. My wife mentioned that something smelled burned when she got out of the truck, maybe it was mostly on the passenger side. Wondering if it also could be the DPF regeneration (burning soot)?
 
So this heater is like having one of those portable electric heaters in your your house that you might use in your bedroom?
 
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