Audi a4 heater not blowing hot: Here’s how to Fix

It is not a comfortable thing to drive a car that has heater issues. The scenario may be like this: you are driving your car, and unexpectedly it starts producing cold air rather than blowing out heat. 

It seems an unbearable issue to run with right? Yes, it is. 

But, here you have solutions. Just keep reading the article until the end. 

First of all, you have to know the common problems and potential causes of a car heater. Then go for the solution as we recommend. 

Let’s start figuring out what to do when you find your Audi A4 heater not working.

Common Reasons of Audi A4 Heater Problems

There are several reasons for which you may find your Audi A4 heater is not working. In most cases, it happens for a broken motor of heater blower, a failed thermostat, or a faulty heater blower motor resistor.

Common Symptoms of the Audi A4 Heater for Not Working & How To Fix

  • Heater Blower Motor IssueACDelco 15-81900 Original Equipment Conditioning

If you find your blower motor is failing to function, then the pressure of air will decrease alarmingly. Though, you may feel warmth or coolness at the vents. That means, once there is a faulty heater blower motor,  then there will be some dysfunctions. 

In addition to this symptom, there may also be a blister noise coming from the passenger floorboard when your car heater or air conditioner is on. It may occur for faulty bearing or fan blades. This noisy sound happens randomly. Sometimes the fan speed changes the sound sometimes doesn’t. 

If you are searching for a heater blower motor, then check our recommended  products from Amazon:

ACDelco 15-81900 Original Equipment Conditioning

Assembly Compatible 2004-2016-2004-2008 Replacement

  • Heater Control Valve IssueAPDTY-140175 Heater Control 2005-2015

You have to replace the heater control valve if your car’s heater control valve goes wrong. A faulty heater control valve may cause leaking of your engine coolant. And thus, your car can get overheated. 

As you are searching for a suitable tool, we have listed our recommended  products from Amazon here:

APDTY-140175 Heater Control 2005-2015

Heater Control Valve-328is-6411837579

  • Heater Core IssueControl Coolant BM5Z-18495-C-BM5Z-18495-BM5Z-18495-B

When the heater core of your car fails, it may carry a smell like an engine coolant into the inside of your car. If you turn the heater on, the smell tends to get nastier than before. This may cause your engine to overheat as well. So, when there is an issue like this, try to repair it soon. Because engine overheating is one of the most injurious issues that are responsible for a further engine defect. 

If your heater core is plugged up,  then the blowing air won’t be very hot. 

Check our recommended  products from Amazon here:

Control Coolant BM5Z-18495-C-BM5Z-18495-BM5Z-18495-B

Spectra Premium 93050 Heater-Core

  • Heater Hose IssueDorman 626-111 Heater-Hose-Assembly

Most likely the heater core, the heater hose can also cause your car to smell like engine coolant. When the engine coolant goes through the heater core, your car interior may start to smell like coolant and mildew. Also, the engine may become overheated. The engine coolant might leak onto the car engine, firewall, and the surface.  

Engine overheating is one of the most dangerous issues, it may be caused by cylinder head gasket failure. 

Buy the heater hose from Amazon:

Dorman 626-111 Heater-Hose-Assembly

Gates 28401-Heater-Hose

Read Also: Audi a3 Rear Wiper Not Working: Here’s How to Fix

  • Thermostat IssueStant-45209-SuperStat-Thermostat-Fahrenheit

A faulty thermostat may create two types of issues. The two types are for: stuck open thermostat and stuck closed thermostat. 

A stuck open thermostat makes your car engine cooler than the standard temperature as well as turns the check engine light on. There might be issues with poor fuel mileage as well as a car heater to give cool air.

A stuck closed thermostat may cause your car to be overheated. Try to solve this issue with a new thermostat. If it can’t solve the temperature issue, then go for a further check for other problems.

Check these thermostats on Amazon:



  • Heater Blower Motor Resistor IssueAdapters Harness Sockets Pigtails Headlights

If your car’s blower motor resistor ceases to function, go for the heater blower motor replacement then. It may cause huge problems in the whole system. 

To replace the heater blower motor resistor, you may check Amazon. Our recommendations are:

Adapters Harness Sockets Pigtails Headlights

Resistor Chevroleet Avalanche Silverado-2003-2006

Final Verdict

If you face the problem of an Audi A4 heater not working, you just have to follow the steps. Heater problems will turn out to be a very annoying issue for you while driving your car in winter. 

Therefore, once there is any issue like this, you should try to solve the problem as soon as possible.

By following the above steps, you will be able to repair it by oneself.  And if you love our recommended products, don’t hesitate to buy from Amazon.

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