1979-1988 Volvo 244 Engine Coolant Temperature Sensor: A Comprehensive Guide
Understanding the critical sensor that controls your Volvo 244's engine behavior and fuel mixture.
- Confirm you are replacing the correct part: the two-wire ECU sensor causes running problems, while the one-wire sender affects the gauge.
- Symptoms of a bad ECU sensor include poor MPG, black smoke, rough idle, and hard starting.
- Access is difficult under the intake manifold; many owners remove the manifold for easier replacement.
- For best results, choose the OEM supplier (Bosch) or a reputable aftermarket brand for this critical electronic part.
Is a Failing Coolant Sensor the Source of Your Volvo 244's Problems?
A faulty Engine Coolant Temperature (ECT) sensor can cause frustrating and confusing issues with your 1979-1988 Volvo 244. Because it sends critical data to the fuel injection computer, a bad sensor can make the car run poorly. It might incorrectly tell the ECU that the engine is always cold, leading to wasted fuel and poor performance. Conversely, if it fails to send a "cold" signal, you may have trouble starting the engine from cold. Given the age of these vehicles, the ECT sensor is a common failure point that can mimic other fuel system or ignition problems.
A Common Mistake: Two Different Temperature Sensors
Your Volvo 244 has two separate sensors in the cylinder head under the intake manifold. It is essential to identify which one you need to replace.
- ECU Coolant Temperature Sensor: This is a two-wire sensor that communicates with the fuel injection computer. If you have symptoms like poor fuel economy, rough running, or hard starting, this is the sensor that needs attention. It is typically located under the #3 intake manifold runner.
- Gauge Temperature Sender: This is a single-wire sender that only operates the temperature gauge on your dashboard. If your gauge is inaccurate but the engine runs fine, this is likely the part that has failed. It is usually found under the #2 intake manifold runner.
Choosing the Right Aftermarket Sensor
When it comes to electronic parts for older Volvos, quality and reliability are key. The original equipment (OEM) sensor was made by Bosch, and it is the most recommended choice for longevity among Volvo enthusiasts. However, several tiers of aftermarket parts are available.
- OEM Supplier (Bosch): Generally considered the best option for fit and long-term reliability.
- Premium Aftermarket (e.g., Beck Arnley, Standard Motor Products): These brands often provide a quality alternative to OEM and are a reliable choice.
- Budget Aftermarket (Generic "Replacement" brands): While the low price is attractive, the reliability of budget-friendly electronic sensors can be inconsistent. Some owners report premature failure with the cheapest options. For a critical sensor like the ECT, spending a little more for a reputable brand is often a wise investment to avoid future issues.
Known Issues, Recalls, and Service Bulletins
Searches of the National Highway Traffic Safety Administration (NHTSA) database show no specific recalls or technical service bulletins (TSBs) for the engine coolant temperature sensor on the 1979-1988 Volvo 244. Any running issues are typically due to age-related failure of the part itself or its wiring connector.
Part & Labor Cost Estimate
| Part Type | Estimated Cost |
|---|---|
| New Aftermarket | $17.82 |
| New OEM (Bosch / Genuine Volvo) | $35 - $55 |
| Shop Labor | $120 - $250 |
Frequently Asked Questions (FAQ)
Is it hard to replace the ECT sensor on a Volvo 244?
Yes, it can be challenging. The sensor is in a tight spot under the intake manifold. While some can replace it with small hands and special tools like a swivel socket, many DIY mechanics find it much easier to remove the intake manifold for clear access. This makes it a moderately difficult job for the average DIYer.
My temperature gauge is acting weird, but the car runs fine. Is it the ECT sensor?
Probably not. If the engine runs well but the dashboard gauge is the only problem, the issue is almost certainly the single-wire temperature *sender* for the gauge, not the two-wire ECT sensor for the computer.
Do I need to drain the coolant to replace the sensor?
You will lose some coolant when the sensor is removed. While you don't have to drain the entire system, having a drain pan ready is a good idea. Topping off the coolant after the replacement will be necessary.
What is the difference between the K-Jetronic and LH-Jetronic sensors?
The 1979-1988 model years included a switch from mechanical K-Jetronic to electronic LH-Jetronic fuel injection around 1982. While their function is similar, the specific sensors may have different resistance values and electrical connectors. It is critical to ensure you are buying the correct part for your vehicle's specific year and fuel system.
Technical Specifications
OEM Part Numbers: 460191 1346030 1332396
Two-wire sensor for fuel injection ECU. Location: Under intake manifold, typically below #3 runner.
The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.