If my coolant sensor is faulty how long can I drive my car before it breaks down?

Could be any of the following: faulty coolant temperature sensor, make sure fan is kicking on, and lastly it could be faulty coolant level sensor

run fault codes for faulty sensors. Check coolant level at the radiator cap (not the reservoir). There is a sensor that is shutting down the engine from an over heat situation.

OVERHEATING CAN BE CAUSE BY MANY THINGS LIKE FAULTY THERMOSTAT AND FAULTY RADIATOR PRESSURE CAP,TOO MUCH WATER IN COOLANT SYSTEM NEED 50 / 50 WATER AND ANTIFREEZE.LOOK FOR WATER PUMP WEEP HOLE LEAK, IF COOLANT LEAKING OUT WEEP HOLE WATER PUMP BAD NEED REPLACING.CHECK FOR LOW COOLANT LEVEL, YOUR RADIATOR OVERFLOW JUG SHOULD HAVE COOLANT AT THE FULL COLD MARK IF NOT KEEP ADDING COOLANT INTO COOLANT OVERFLOW JUG UNTIL COOLANT STOP DROPPING AND FULL COLD MARK, IF OVERFLOW COOLANT JUG WAS EMPTY RADIATOR IS LOW ON COOLANT.WHICH CAUSE AIR IN COOLANT SYSTEM KEEPING THE ENGINE COOLANT TEMPERATURE SENSOR FROM BEING SUBMERGE IN HOT COOLANT WHICH TURN ON THE COOLANT FANS.WHEN ENGINE COOLANT TEMPERATURE GET CERTAIN SET TEMPERATURE LIKE 190 DEGREES THE PCM AND COOLANT SENSOR WILL TURN ON COOLANT FANS, IF VECHICLE OVERHEATING COOLANT FANS NOT WORKING EITHER YOU HAVE FAULTY ENGINE COOLANT TEMPERATURE SENSOR CHECK COOLANT FANS FUSE AND RELAYS. YOU CAN CODE SCAN CAR TO SEE IF YOU HAVE FAULTY PCM, FAULTY ENGINE COOLANT TEMPERATURE SENSOR OR FAULTY COOLANT FAN RELAY.IF COOLANT FAN AND ENGINE COOLANT TEMPERATURE SENSOR OKAY,YOU HAVE CORRECT COOLANT LEVEL IN COOLANT SYSTEM, THERMOSTAT AND RADIATOR PRESSURE CAP BEEN REPLACED, YOU COULD HAVE BLOWN HEAD GASKET CHECK ENGINE OIL LOOKS LIKE MILK SHAKE HEAD GASKET BLOWED ALSO WHEN HEAD GASKET BLOWED YOU CAN DRIVE CAR SHORT DISTANCE START OVERHEATING AND YOU LOOSE ENGINE POWER SUSPECT BLOWED HEAD GASKET.

First off you need to make sure you replaced the right sensor alot of vehicles are equipped with two coolant sensors on feeds the computer information and the other sensor registers temperature on your gauge so make sure you replaced the right one.If you did replace the right one then possibilities are a break in the wire from the coolant sensor to the temperature gauge on your dash also could be your temperature gauge on your dash could be faulty.

CHECK FOR LOW COOLANT LEVEL.IF COOLANT LEVEL OKAY.SCAN VECHICLE FOR FAULTY COOLING FAN OR RELAY.AND SCAN FOR FAULTY COOLANT TEMPERATURE SENSOR.

Faulty thermostat is most common problem. Blue lamp on indicates coolant not reached operating temperature.

Blue Lamp hould stay out when coolant reaches operating temperature. VW have updated the Coolant Temperature Sensor. Thermostat is opening too long allowing coolant to cool below operating temperature tripping Blue Lamp..

New sensor should be GREEN in color and lives on the coolant hose running back across the rear of the engine.

When getting one replaced make sure you get the 'O' ring and new plastic clip to hold it in, along with the Sensor. They are orderable separately and your VW parts guy will not offer 'O' ring and clip unless you ask.

Check coolant is circulating into the bottle on the inner fender .
These engines also suffer from failure of the coolant pump when the plastic impeller breaks up or comes off the drive shaft. this causes overheating.

did you replace both coolant and engine temp sensor? Thermostat? Plugged exhaust or faulty egr is another possibility

16501/P0117 - Engine Coolant Temperature Sensor (G62): Signal too Low Possible Symptoms

• Difficulties with starting a cold engine.
• Starting the engine when engine is warmish or warm, idle rpm immediately is 1200 - 3000 rpm.
• RPM at idle is irregular.
• With all engine temperatures seldom idle rpm will vary between 900 - 1000 rpm.
• With engine warm (90 °C) the engine temperature suddenly drops (70 °C) and slowly comes back to 90 °C.
• Bad acceleration during warming up.
  • Diesel: an indication is extreme long time burning time of the glow indication light.

Possible Causes

• The electrical signal coming from G62 is too low
• Wiring and/or connections faulty (short circuit?)
• Engine Coolant Temperature Sensor (G62) faulty

Possible Solutions

• Check wiring and connections
• Check / Replace Engine Coolant Temperature Sensor (G62)

Special Notes

• In MY 1995-2002 (?) in Europe at VW-cars the G2/G62 had the bad reputation of breaking down often. The default G2/G62 is black and all replacements are green.

Problem solved
Pulled out instrument cluster, un pluged, connected back and reinstalled. Bingo! everything works fine. Faulty connection maybee???

sounds like your thermostat may be stuck shut, blocking the flow of coolant through your engine block. it cools down again because of the cool air coming through the rad.