Our 01 devill dts is overheating new radiaor,

You have trapped air in the cooling system, purge the air out of the system. You can do this by raising the car front end as high as possible and filling the coolant recovery tank to the brim leave the cap off, then run engine until it reaches operating temperature, then shut it down and run cold water over the radiator core, the coolant tank will be sucked dry most likely as the air is purged and replaced by coolant.

It can be faulty coolant temperature sensor.Its not sensing exact coolant heat temperature so its overheating then required level.

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Get the coolant pressure tested, its definitely leaking coolant. You will need to get the coolant running line.

Pressure test will help you to know from where exactly coolant/refrigerant is getting leaked.

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For complete step by step troubleshooting i suggest you to go through the help links mentioned below :----

Click the link below :-----

Coolant enters in transmission on Toyota Land cruiser?

http://schematicsdiagram.blogspot.com/2012/01/coolant-enters-in-transmission-on.html

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1991 Toyota Camry: Order Coolant Bypass Tube?

http://whatisbyme.blogspot.in/2012/05/1991-toyota-camry-order-coolant-bypass.html

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2002 Toyota Camry: Puff of Blue or White Smoke while Starting?

http://whatisbyme.blogspot.in/2012/05/2002-toyota-camry-puff-of-blue-or-white.html

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1994 Toyota Camry: Coolant Leak?

http://technoanswers.blogspot.in/2012/04/1994-toyota-camry-coolant-leak.html

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2006 Cadillac DTS: COOLANT LEAK AT DRIVER SIDE NEAR FIREWALL?

http://schematicsdiagram.blogspot.in/2012/04/2006-cadillac-dts-coolant-leak-at.html

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MAF, IAT, MAP and Coolant Level Sensor problem all together on Mazda MPV?

http://schematicsdiagram.blogspot.com/2011/12/maf-iat-map-and-coolant-level-sensor.html

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GMC Engine Coolant Temperature (ECT) Sensor Replacing?

http://schematicsdiagram.blogspot.com/2011/12/gmc-engine-coolant-temperature-ect.html

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Loosing Coolant?

http://whoisbyme.blogspot.in/2012/06/loosing-coolant.html

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Coolant temperature sensor dies again and again?

http://schematicsdiagram.blogspot.com/2012/01/coolant-temperature-sensor-dies-again.html

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2000 Daewoo Lanos: Where to Add Coolant?

http://repairhelpcenter.blogspot.in/2012/06/2000-daewoo-lanos-where-to-add-coolant.html

Blue Water Warning Light on Dash?

http://whatisbyme.blogspot.in/2012/07/blue-water-warning-light-on-dash.html

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Replacing Oldsmobile Engine coolant sensor?

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How to test Engine coolant temperature sensor?

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Replace Coolant Sensor Module on Oldsmobile?

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These details will help.

Thanks.

bad water pump

Overheating is not always caused by a bad water pump or bad engine firing timing.

The most common causes are:

• faulty radiator cap: steam/water will be escaping from the caps when engine is hot or oveflow tank overflows or empty!
  
• crack cylinder head gasket: check when engine is cold thru radiator cap hole for milky oil in water radiator or large bubbles in radiator water after starting engine. Also check if water steam comes out of exhaust.
  
• cylinder head itself: same symtoms as for gasket above.

Hope it helps you find your problems.

Either the coolant is escaping, or not circulating. If there is coolant in a puddle under where the car is usually parked, then I would look above that point, track the leak back to its origin and fix the leak. If the exhaust smells of coolant, then you need a real shop repair for a gasket or worse.
If the coolant is not circulating then I would check for a bad water pump or a blocked radiator. Lots of the L Saturns had leaking heater cores, a slippery wet passenger floor and stink was the indicator.

remove expansion tank cap (if fitted) take off the highest hose clip in the system and fill from there if you have an air lock in the system it will be obvious...after connecting back up, fill tank with neat anti freeze.(if tank is higher than hose, fill tank as air is expelled from the pipe.)

replace radiator cap system depends on good pressure to keep from overheating

Per Chilton's Repair Manual: You're dealing with aluminum so pay careful attention not to exceed recommended torque.

4.5L And 4.9L Engines

1. Disconnect the negative battery cable.
   
2. Drain and recycle the engine coolant.
   
3. Remove the air filter assembly. Disconnect and remove the coolant recovery tank.
   
4. Disconnect and remove the cross brace.
   
5. Remove the water pump pulley bolts.
   
6. Remove the serpentine drive belt and the water pump pulley.
   
7. Remove the water pump-to-engine bolts and the pump.
   

Water pump assembly—4.5L and 4.9L engines
To install:

1. Clean the gasket mounting surfaces.
   
2. Place a new gasket over the water pump studs.
   
3. Install the water pump. Tighten the water pump bolts as follows:
   
   1. Water pump-to-engine Torx® bolts to 30 ft. lbs. (40 Nm)
      
   2. Water pump-to-engine stud nuts to 5 ft. lbs. (7 Nm)
      
   3. Hex head bolts to 30 ft. lbs. (40 Nm)
      
   4. Remaining hex head bolts to 5 ft. lbs. (7 Nm).
      
4. Install the water pump pulley. Install the water pump pulley bolts finger-tight.
   
5. Install the serpentine drive belt.
   
6. Tighten the water pump pulley bolts to 22 ft. lbs. (30 Nm).
   
7. Install the cross brace.
   
8. Install and connect the coolant recovery tank. Install the air filter assembly.
   
9. Connect the negative battery cable.
   
10. Fill cooling system and check for leaks. Start the engine and allow it to come to normal operating temperature. Recheck for leaks. Top-up the coolant.
    

Hi,
If the car is overheating it could be due to a thermostat which is stuck in the closed position, a failed water pump or just a slack belt driving it. I think there will be a "little" tube carrying coolant from the engine to the coolant expansion tank, and if you run the engine with the filler cap removed you should see water coming through that pipe IF the rump is running. A failed water pump will not necessarily leak, it just won't pump the water round the engine.

Always take care when dealing with a pressurised cooling system on an overheating engine - the water may well be above boiling point.

If you run the engine without coolant the cylinder head may well warp and repair bill will be huge.

Hope this helps you a bit. D