Inconsistent cooling If the ambient temperature sensor fails or is sending out an inconsistent signal, then the AC system may have trouble maintaining cool and comfortable cabin temperatures.
Table of Contents
What are the symptoms of a faulty temperature sensor?
- Poor Fuel Economy.
- Irregular Temperature Readings.
- Black Smoke from Your Exhaust.
- Your Engine is Overheating.
- Your Check Engine Light is On.
How do I check the engine temperature on my BMW e90?

Where is the temperature sensor on a BMW?

What is the normal engine temperature BMW e90?
Registered. Normal operating temperature is 90 degrees, if you’re egr stat has been replaced and it’s only getting to 70 then your main stat is goosed and needs replacing.
What happens when engine temperature sensor goes bad?
A faulty sensor can cause the fuel mixture to adjust. This causes the engine to shake or vibrate when the vehicle is at low speed and can even bring about strange behaviors, power losses, etc. Engines are highly sensitive, especially to inappropriate air-fuel mixtures at idle.
Can I drive without coolant temperature sensor?
It is very dangerous to drive a car with no coolant. Driving your car without coolant can cause engine overheating and an overheated engine can trigger significant damage to core engine parts. When the car runs, the coolant must flow around the engine block in order to keep the engine temperature under check.
How do I know if my e90 is overheating?
- Engine Overheating Light.
- Thumping Noises.
- Engine Ticking Sound.
- Hood is Hot to the Touch or Steam Coming from Under the Hood.
- Engine Coolant Leak.
- Coolant System Restriction.
- Malfunctioning Water Pump.
- Incorrect Coolant Type.
Why is my BMW engine so hot?
The four most common reasons for high engine temperatures include low coolant levels, pockets of air in the cooling system, cooling fan malfunction, or debris in the radiator.
What happens when a BMW overheats?
Signs of Overheating First, you will see steam (it may look like smoke) coming from under the hood. Your dashboard engine temperature gauge may also increase to “H” or go into the red. Consult your owner’s manual for the specific symbol for your BMW model.
Where is the engine temperature sensor located?
The coolant temperature sensor will be located directly behind the coolant pipe. In most modern cars and vehicles, this is present behind the right cylinder head that is located right underneath the air intake pipe.
How do you test a coolant temperature sensor?
Gently lower the end of the sensor into the water until the entire device is fully submerged. Wait a minute or so for the screen to give you a reading of the cold water. Once you have a reading, write down the measurement for reference. A common reading for a temperature sensor in cold water is around 5 volts.
What is normal coolant temperature for a BMW?
Normal Temperature engine temperature gauge Most experts agree that your engine should run between 195 degrees and 220 degrees.
What temperature does a BMW thermostat open?
Once the temperature of the coolant rises to between 180 and 195 F (82 – 91 C), the thermostat starts to open, allowing fluid to flow through the radiator.
Why does my car temp go up and down?
The primary reason your car temperature gauge goes up and down while driving is simply because a component in your cooling system is not functioning correctly. This could be the thermostat valve, radiator hoses, radiator fan, temperature gauge, or the coolant itself that circulates around and cools off the engine.
Why doesn’t my BMW have a temperature gauge?
BMW opted for no coolant gauge bc the gauge needle would move around too much – for the average driver. And so not to confuse the average driver, BMW decided not to provide an coolant gauge. We all just wait until we see the oil temp gauge start to come up to temp, before we start to hammer it!
Can you clean a engine coolant sensor?
In most cases, sensors for your automobile will need to be replaced if they fail, but depending on the type of sensor and its location or function, some can be cleaned and reused.
Can a temp sensor affect engine starting?
If you have starting problems and the ‘check engine’ light doesn’t come on, you may have a bad engine coolant temperature sensor (ECT). They’re quick and easy to replace.
How long does a coolant temperature sensor last?
Often, the engine coolant temperature sensor must be replaced at about 100,000 miles. If you don’t properly maintain the engine cooling system, the sensor could fail much earlier.
Can a bad temp sensor cause overheating?
If the coolant temperature sensor malfunctions, it could cause your car engine to get overheated. While sometimes a faulty sensor sends a permanent cold signal to the engine, it can also send a permanent hot signal.
Can I use water instead of coolant?
Technically speaking yes you can use plain water in your cooling system but it isn’t recommended as a long term solution and certainly not in extreme weather conditions. The problem with using water in your cooling system is that water freezes at 0ยฐC.
How do I know if my BMW thermostat is bad?
- High temperature readings. The main symptoms of a failing thermostat are related to engine overheating.
- Erratic changes in temperature.
- Leaking coolant.
- Increased fuel consumption.
- Unusual noises.
How do I know if my BMW water pump is bad?
- Coolant Leaks.
- High-pitched Whining Sounds.
- Engine Overheating.
- Steam Coming From The Radiator.
- Higher Mileage.
- Routine Maintenance.
- Regular Coolant Changes.
- Any Change In Your BMW’s Performance.
How do you cool down a BMW engine?

How can I cool down my engine fast?
Put your car in neutral or park and then rev the engine. This makes the fan and the water pump work faster, which pulls more air and more water through your car’s radiator. This increased circulation cools down the engine. Pull over and open the hood.