2004 DODGE RAM 1500 GAS engine overheat

Catalytic Converter
The catalytic converter requires the use of unleaded fuel
only. Leaded gasoline will destroy the effectiveness of the
catalyst as an emission control device.
Under normal operating conditions, the catalytic con-
verter will not require maintenance. However, it is im-
portant to keep the engine properly tuned to assure
proper catalyst operation and prevent possible catalyst
damage.CAUTION!
Damage to the catalytic converter can result if your
vehicle is not kept in proper operating condition. In
the event of engine malfunction, particularly involv-
ing engine misfire or other apparent loss of perfor-
mance, have your vehicle serviced promptly. Contin-
ued operation of your vehicle with a severe
malfunction could cause the converter to overheat,
resulting in possible damage to the converter and the
vehicle.
NOTE:Intentional tampering with emissions control
systems can result in civil penalties being assessed
against you.
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WARNING!
A hot exhaust system can start a fire if you park over
materials that can burn. Such materials might be
grass or leaves coming into contact with your ex-
haust system. Do not park or operate your vehicle in
areas where your exhaust system can contact any-
thing that can burn.
In unusual situations involving grossly malfunctioning
engine operation, a scorching odor may indicate severe
and abnormal catalyst overheating. If this occurs, the
vehicle should be stopped, the engine shut off and the
vehicle allowed to cool. Thereafter, service, including a
tune-up to manufacturer's specifications, should be ob-
tained immediately.
To minimize the possibility of catalyst damage:
²Do not shut off the engine or interrupt the ignition
when the transmission is in gear and the vehicle is in
motion.
²Do not try to start engine by pushing or towing the
vehicle.
²Do not idle the engine with any spark plug wires
disconnected or removed, such as when diagnostic
testing, or for prolonged periods during very rough
idling or malfunctioning operating conditions.
Emission-Related Components
Positive Crankcase (PCV) Valve
Proper operation of the crankcase ventilation system
requires that the PCV valve be free of sticking or plug-
ging from deposits. Deposits can accumulate in the PCV
valve and passages with increasing mileage. Have the
PCV valve, hoses, and passages checked for proper
operation at the intervals specified. If the valve is
336 MAINTAINING YOUR VEHICLE

The radiator normally remains completely full, so there is
no longer a need to remove the coolant pressure cap
except for checking coolant freeze point or replacement
with new antifreeze coolant.
WARNING!
Never add coolant to the radiator when the engine is
overheated. Do not loosen or remove pressure cap to
cool an overheated engine! The coolant is under
pressure and severe scalding could result.
Drain, Flush And Refill
At intervals shown on the Maintenance Schedules, the
system should be drained, flushed and refilled. Refer to
your dealer or consult a service manual for proper
procedures.
Adding Coolant
When adding coolant or refilling system, a 50% solution
of ethylene glycol antifreeze coolant in water should be
used. Higher concentrations (not to exceed 65%) are
required if temperatures below -34 FÉ (-37 CÉ) are antici-
pated. Use only high purity water such as distilled or
deionized water when mixing the water/antifreeze solu-
tion. The use of lower quality water will reduce the
amount of corrosion protection in the engine cooling
system. Please note that it is the owner's responsibility to
maintain the proper level of protection against freezing
according to the temperatures occurring in the area
where the vehicle is operated.
NOTE:Mixing coolant types will decrease the life of the
engine coolant and will require more frequent coolant
changes.
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7

When additional coolant is needed to maintain the
proper level, add the recommended concentration of
antifreeze and water to the coolant bottle. Do not overfill.
NOTE:Failure to follow the antifreeze concentration
and replacement recommendations, or failure to use
antifreeze formulated to prevent corrosion of all cooling
system metals, may result in radiator plugging, overheat-
ing, or cooling system leaks such as in core hole plugs.
WARNING!
Never add coolant to the radiator when the engine is
overheated. Do not loosen or remove pressure cap to
cool an overheated engine. The coolant is under
pressure and severe scalding could result.
Recommended Engine Coolant
Refer to Recommended Fluids, Lubricants and Genuine
Parts for correct fluid type.
CAUTION!
Mixing of coolants other than specified (non-HOAT),
may result in engine damage that may not be covered
under the new vehicle warranty, and decreased cor-
rosion protection. If a non-HOAT coolant is intro-
duced into the cooling system in an emergency, it
should be replaced with the specified coolant as soon
as possible.
Do not use plain water alone or alcohol base anti-
freeze products. Do not use additional rust inhibitors
or antirust products, as they may not be compatible
with the radiator coolant and may plug the radiator.
This vehicle has not been designed for use with
Propylene Glycol based coolants. Use of Propylene
Glycol based coolants is not recommended.
346 MAINTAINING YOUR VEHICLE