BRAND NEW *OEM Quality* Coolant Temperature Sensor to suit early Holden HD and HK, including the HK Monaro, with the red motor six and the 253 V8.

Restoring or maintaining an early Holden and need a replacement coolant temperature sensor? Check the thread and plug details below against your engine. Packed and shipped from Cranbourne VIC.

TO SUIT

For Holden HD 179 cu.in 2.9L red motor (1965-1966)
For Holden HK 161 and 186 cu.in red motor and 253 V8 (1968-1969)
For Holden HK Monaro 161 and 186 cu.in red motor (1968-1969)

FITMENT CHECK

3/8 inch x 18 NPTF thread with a 2-terminal oval connector. Compare with the sensor on your engine before ordering.

OEM PART NUMBERS

19189501
89054729

OTHER PART NUMBERS

CS885
CTS1033

PACKAGE INCLUDES

1 x Coolant Temperature Sensor - 2-pin oval connector.

ABOUT THIS SENSOR

This sensor screws into the coolant passage and changes its electrical resistance as the engine warms up. That signal is used to show or control engine temperature.

Over time the element corrodes or cracks and the reading drifts. A wrong reading can hide a real overheating problem or show one that is not there.

COMMON SYMPTOMS OF FAILURE

Temperature reading stuck on cold
Temperature reading too hot for actual engine temperature
Erratic or jumping temperature reading
Coolant weeping from the sensor thread

[02/65 - 03/66] EARLY HOLDEN HD 2.9L 6cyl 179 cu.in Red 86kW
[04/68 - 04/69] EARLY HOLDEN HK 2.6L 6cyl 161 cu.in Red
[04/68 - 04/69] EARLY HOLDEN HK 3.0L 6cyl 186 cu.in Red
[04/68 - 04/69] EARLY HOLDEN HK 4.2L V8 253 cu.in Red
[04/68 - 04/69] EARLY HOLDEN HK MONARO 2.6L 6cyl 161 cu.in Red
[04/68 - 04/69] EARLY HOLDEN HK MONARO 3.0L 6cyl 186 cu.in Red

How do I test a coolant temperature sensor?

The most common test is to measure the sensor resistance with a multimeter at a known coolant temperature and compare against the manufacturer resistance curve. A cold engine (20 degrees C) typically reads 2,000 to 3,000 ohms and drops to around 200 to 300 ohms at operating temperature (90 degrees C). An OBD2 scanner showing a fixed temperature reading that does not change as the engine warms up is also a strong indicator of sensor failure.

Can a faulty coolant temperature sensor cause my engine to overheat?

Indirectly yes. If the sensor reports a lower temperature than actual, the ECU may not activate the cooling fan at the correct time, allowing the engine to overheat. It can also suppress the dashboard warning light, meaning you may not be alerted until the engine is already at a dangerously high temperature. Replace a suspected faulty sensor promptly.

Do I need to drain the coolant to replace the sensor?

Not always - many coolant temperature sensors can be replaced quickly with minimal coolant loss if you work fast and have a replacement ready to thread in immediately. However on some vehicles the sensor location requires partial coolant drainage. Check the sensor position on your specific engine before starting. Always use fresh coolant when topping up after replacement.

What are the symptoms of a faulty coolant temperature sensor?

Symptoms include poor fuel economy, black smoke, engine overheating warning, incorrect temperature gauge reading, hard starting when cold, and rough idle. Fault codes P0115 to P0119 are commonly associated with coolant temperature sensor faults.

Is it safe to drive with a bad coolant temperature sensor?

A faulty coolant temperature sensor can cause the ECU to run rich fuel mixtures and prevent the cooling fan from operating correctly, risking engine overheating. Replace it promptly - it is a low-cost part that can prevent expensive engine damage.

How do I know if my coolant temperature sensor or my thermostat is faulty?

A faulty thermostat typically causes the engine to overheat or never reach operating temperature. A faulty coolant temp sensor causes incorrect gauge readings and running issues but the coolant itself may be at the correct temperature. An OBD2 scanner showing live coolant temp data helps distinguish between the two.

Are there two coolant temperature sensors on my vehicle?

Many vehicles have two sensors - one for the ECU (engine management) and one for the dashboard temperature gauge. They look similar but are not interchangeable. Check your vehicle's service manual or contact us with your vehicle details to confirm which sensor you need.

Identification
SKU	CTS183
Brand	Aftermarket OEM Replacement
Part Numbers
Part Number	19189501
Reference OEM Number	19189501
Other OEM Numbers	19189501, 89054729
Related Part Numbers	CS885, CTS183, CTS1033
Product Specifics
Sensor Type	ENGINE COOLANT TEMPERATURE SENSOR
Type	Sensor
Features	Direct Fit
Manufacturer Warranty	1 Year
Thread Size	3/8"x18 NPTF
Number of pins	2 -pin connector
Connector Shape	oval
Socket colour	Black
Other Details
Note	Always verify fitment using your vehicle's OEM part number.
Unit Of Measure	ea