Tip & How-To about Volkswagen Golf

VW Golf 3 Cold start problem, not idling when cold

Wait for your car to cool down before attempting this procedure. Standing in front of your car with the bonnet open, you will see your radiator closest to the grill/front section of your vehicle. Next, follow the thick black hose running to your engine header. Closest to the header of your engine you will notice a T-piece connection section (plastic) with an electric plug on the top of the housing. The T-Piece with the plug pointing upwards, is connected to a "cold start" sensor. (Normally having 4 wires connected to it) There should be a clip holding it down in its housing. That is your hot & cold start sensor. You can remove this part and take it to your nearest parts supplier as a sample. Nearly everybody stocks them nowadays. Replace it and your troubles will be over. To remove, check for a plastic or metal split pin lookalike ( looks like a U clip as wide as the housing) just below the electric plug, on the side of the housing. Simply slide the clip out to the side using a screwdriver, and lift out the sensor using a long nose pliers. Place the long nose pliers inside the switch section and jiggle from left to right. The sensor is only sealed with a rubber O-ring, and should come out fairly easy after the clip has been removed. Replace with new and replace plug. All your cold start problems should be over
PS. Please do not remove this when the car is hot!

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how do i open my bonnet with no cable


Try using a long rod from under the car up past the front of the radiator to activate the lock. You may need a friend to push down on the bonnet to help in this operation.

Apr 27, 2013 | Cars & Trucks

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I have a 99 Chrysler Cirrus with a V6 2.5L. I have steam comming out from under the hood on the passenger side front of the car. Any suggestions?


Hello sounds like you have overheated your engine or cooling system hose or radiator is leaking let your engine completely cool down open radiator cap and refill you engine coolant close it up and restart and watch for your leaking point this could be a rad cap.radiator hose or the radiator tank and at this point you can access the problem and feel if you can attempt to repair or not.Or you can let the car completely cool down top up cool;ant in radiator and take the car into a garage.

Dec 27, 2010 | 1999 Chrysler Cirrus

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92 Corona auto - fill radiator with water - drive 90 minutes did 150 k no serious hills- temperature guage needle moved up after moving from 100 k to 50 k - no water - temperature guage just about in red - stop -wait 10 minutes refill water - when I opened bonnet - spray on bonnet left hand side - no water dripping under car


sounds like a coolant hose has a pin-hole or burst slightly open. pressure test cooling system or if you do not have a tester ----fill system with water and with bonnet open run engine untill it gets hot, builds pressure and starts leaking ,just keep an eye as where it leaks,

Dec 20, 2009 | 1992 Toyota Corolla

1 Answer

air in cooling system


Make sure the engine is cold and and remove the radiator cap. Top off the radiator and coolant recovery tank. Put the cap on the recovery tank but leave the radiator cap off. Start the engine. Monitor the temp. gauge about every 20 seconds. Carefully grab the upper radiator hose in 90 second intervals and very gently squeeze it a few times to help release the trapped air.The coolant level should drop visibly into the radiator as the thermostat opens. Now bring the rpm up to about 1800 and HOLD it there while you top off the system and then tighten down the radiator cap completely before you drop the engine rpm. I recommend using a friend to help with this procedure. Then let the car run as you check for the upper hose to feel warm and solid to the touch. Watch the gauge. The reading should be steady. If it starts to overheat, shut off the engine and wait for it to cool down. Repeat the procedure if necessary

Jul 01, 2009 | 1994 Mitsubishi Diamante

1 Answer

I replaced the alternator on my 2003 Range Rover


I Suspect that you have AIR in your COOLING SYSTEM Fallow Procedures BELOW to Insure there is NO AIR IN COOLING SYSTEM


Draining and Filling Cooling System

Draining Procedure

Important: Do NOT add any engine coolant supplement sealant pellets to the cooling system. Drain and refill the engine cooling system every 5 years or 240,000 km, (150,000 mi) , whichever occurs first.

  1. Park the vehicle on a level surface.
  2. Remove and clean the coolant recovery reservoir.
Caution: Refer to Radiator Cap Removal Caution in Service Precautions.

  1. Remove the radiator cap when the engine is cool:
3.1. Slowly rotate the cap counterclockwise to the detention tab. Do not press down while rotating pressure cap. 3.2. Wait until any residual pressure, indicated by a hissing sound, is relieved. 3.3. After all hissing stops, press down on the radiator cap and rotate the cap counterclockwise in order to remove the cap.
Important: Recover and store used coolant in a used coolant holding tank and submit the used coolant for recycling on a regular basis. Do NOT pour used coolant down the drain. Ethylene glycol antifreeze is very toxic. Disposing of ethylene glycol into the sewer system or ground water is both illegal and ecologically unsound.

  1. Place a drain pan under the radiator drain valve in order to collect all of the used coolant.
  2. Open the radiator drain valve located at the bottom of the radiator tank. If only partial cooling system draining is required, drain enough coolant to perform the procedure.
  3. Open the air bleed valve on the thermostat housing 2 full turns
    1. Open the air bleed valve above coolant pump 2 full turns.
    2. Place a drain pan under the engine block drains in order to collect the used coolant.Important: Allow the coolant to drain completely.

      1. Remove both of the engine block drains.
        • The front left engine block drain is located between the starter motor and the engine oil filter.
        • The rear right engine block drain is located near the crankshaft position sensor.
      Filling Procedure
      Reinstall the engine block drains
    3. Close the radiator drain valve,
      1. Install the coolant recovery reservoir. Notice: When adding coolant, it is important that you use GM Goodwrench DEX-COOL or HAVOLINE DEX-COOL coolant. If Coolant other than DEX-COOL or HAVOLINE DEX-COOL is added to the system the engine coolant will require change sooner; at 50,000 km (30,000 mi) or 24 months.
      2. Slowly add a 50/50 mixture of GM Goodwrench DEX-COOL or HAVOLINE DEX-COOL and clean, drinkable water to the radiator until the coolant level is at the base of the radiator fill neck.
      3. Wait for 2 minutes and reinspect the level of the coolant in the radiator. If necessary, add coolant to the radiator until the coolant level is at the base of the radiator fill neck.
      4. Install the radiator cap.Ensure that the radiator cap arrow points toward the radiator overflow tubeImportant: The air bleed valves are brass. Do NOT over-tighten the air bleed valves.

        1. Close the air bleed valve above the coolant pump.
          1. Close the air bleed valve on the thermostat housing.
          2. Fill the coolant reservoir with a 50/50 mixture of GM Goodwrench DEX-COOL or HAVOLINE DEX-COOL and clean, drinkable water. Caution: Refer to Radiator Cap Removal Caution in Service Precautions. Important: If the coolant temperature indicator turns ON, turn the engine OFF immediately and allow the engine to cool. Do NOT remove the radiator cap.
          3. Start the engine and allow the engine cooling fan to cycle on and off 3 times. If the low coolant indicator does not turn OFF and the coolant level is above the Full Cold mark on the coolant recovery reservoir, refer to Engine Coolant Temperature Gage Inaccurate or Inoperative.
          4. Turn off the ignition.
          5. Allow the engine to cool.
          6. Ensure that the engine coolant concentration is sufficient.

Feb 21, 2009 | 2001 Pontiac Aztek

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