When heat is on outside air, exhaust smell. Not when circulating air. Worse when standing behind other cars.
Exhaust smell when heat is on. Can only smell when car is set to bring air in from outside. If set to circulate inside air, no smell. The smell is worse when I'm behind another car.
My car has 116417 miles.
My car has an automatic transmission.
Experienced mechanics share their insights in answering this question :
Hello, thank you for writing in. The vehicle is designed to pull in the air in from around the vehicle to use in heating the air. When on that setting, the engine is pulling in exhaust fumes. This means that the vehicle has an exhaust leak. The leak will need to be found and repaired before the smell will go away. Keep in mind inhaling these fumes is not good as they are toxic. You will want to keep the heating and air conditioning system on recirculate. When you are at a stop and idling, the smell can accumulate because there is less airflow to push the fumes away from the cabin. Finding these exhaust leaks can be done several ways, but repairing them can be difficult. For more help contact our service department.
How to Identify and Fix Common car Problems ?
Our sources include academic articles, blog posts, and personal essays from experienced mechanics :
If you smell exhaust all the time, it`s likely coming from near the front of the system. This could be due to physical damage, or it could be related to the exhaust manifold gasket. If you only smell it when you`re idling, chances are it`s nearer to the back of the system.
The vehicle is designed to pull in the air in from around the vehicle to use in heating the air. When on that setting, the engine is pulling in exhaust fumes. This means that the vehicle has an exhaust leak. The leak will need to be found and repaired before the smell will go away.
If your exhaust has the distinct noxious smell of rotten eggs, sulfur, or sewer gas, it`s likely due to a damaged catalytic converter. When combustion happens in your engine, harmful gases like hydrogen sulfide (which contains sulfur) are created.
You may have a coolant leak if you notice a sweet smell or if your car smells hot, but it`s not overheating. Coolant, also known as antifreeze, keeps the engine at a safe temperature. If there`s a leak and the coolant can`t do its job, the engine may start overheating.
This is most commonly caused by things like leaking fuel injectors, a clogged engine air filter, a bad mass airflow sensor, bad throttle body or bad oxygen sensor.
To fix this problem, you`ll just need the exhaust leak fixed. This could be as simple as reattaching two disconnected parts or welding shut a hole in the exhaust pipe. Or, you may need more significant work on the exhaust system such as replacing a leaking exhaust manifold gasket.
Fumes/Exhaust Smell
If you notice fume-like smells while driving, particularly when you`re idling or driving slowly, pull over immediately and exit the car. The smell of fumes could indicate a leak in the exhaust, meaning dangerous levels of carbon monoxide could be entering the cabin.
Essentially, this smell comes from uncombusted fuel. As mentioned, running rich is the result of a faulty combustion process, and this leftover fuel escapes into the exhaust in all of its stinky, polluted glory. Usually, our catalytic converters prevent the smell from appearing.
The fuel pressure sensor regulates the fuel flow in the engine. A faulty pressure sensor will allow too much oil to reach the catalytic converter. The malfunction in the catalytic converter will emit sulfuric gasses and make your car smell like rotten eggs.
Fumes/Exhaust Smell
If you notice fume-like smells while driving, particularly when you`re idling or driving slowly, pull over immediately and exit the car. The smell of fumes could indicate a leak in the exhaust, meaning dangerous levels of carbon monoxide could be entering the cabin.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
When heat is on outside air, exhaust smell. Not when circulating air. Worse when standing behind other cars.
ANSWER : Hello, thank you for writing in. The vehicle is designed to pull in the air in from around the vehicle to use in heating the air. When on that setting, the engine is pulling in exhaust fumes. This means that the vehicle has an exhaust leak. The leak will need to be found and repaired before the smell will go away. Keep in mind inhaling these fumes is not good as they are toxic. You will want to keep the heating and air conditioning system on recirculate. When you are at a stop and idling, the smell can accumulate because there is less airflow to push the fumes away from the cabin. Finding these exhaust leaks can be done several ways, but repairing them can be difficult. For more help contact our service department.
Gasoline inside the car?
ANSWER : The first concern is whether you could have an exhaust leak or a fuel leak. If leaks of that type exist, they should be repaired as both are safety hazards. Occasionally, just due to the weather, exhaust fumes can get drawn into cabin air. At no time, however, is it normal for significant amounts of raw gasoline to be in the air, or leaking as a liquid, especially on a modern car which has sophisticated systems to capture any potential fugitive emissions of vaporous gasoline. If this was a one-off incident, and just limited to exhaust odor, not to worry but if you regularly detect the distinct odor of raw gasoline, that should be investigated at once because leaking gasoline is a fire/explosion hazard. As far as damage to personal belongings from exhaust or gasoline vapors, in ordinary concentrations and if the exposure is fleeting, there is no damage potential. The reason is gasoline is highly volatile and so evaporates into the atmosphere. However, if you spill liquid gasoline on materials, the non volatile compounds will be around for a long time and indeed will destroy many common materials as gasoline is a highly aggressive solvent. Most of the hazard from gasoline vapors is not to personal property but rather to your health because gasoline contains known, well documented carcinogens such as benzene. So, the bottom line is fleeting exposure to the vapors will not damage property but will damage your health. With regard to leaks (exhaust or gasoline, liquid or vapor), if you desire a safety inspection performed by a certified Mechanic, dispatched by YourMechanic right to your location, please request a comprehensive vehicle safety inspection and the responding certified mechanic will address all of your concerns and look at the condition of your entire vehicle. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.
A/C and heat are not working properly. Car blows heat in summer and cool air in winter.
ANSWER : Common causes of no cabin heat include malfunctioning blend door(s) (part of the in-dash ventilation network), a faulty or stuck heater control valve, a plugged heater core, stuck open engine cooling thermostat, collapsed hoses, and low coolant level. The cost to resolve the problem depends on which of the foregoing faults is the cause. If you desire a diagnostic to determine exactly why there is no cabin heat, please request a non functioning cabin heater diagnostic and the responding mechanic will come right to your location and get this resolved for you promptly.
With regard to your air conditioning system, if merely re-charging the system restored normal operation but the a/c ceased to function after a month or so, that scenario typically suggests a leak. Some leaks are really cheap to repair, like if a couple o-rings need to be replaced in system piping but if the leak is at the compressor shaft seal, that repair is more costly. It is not expensive to find the leak and diagnose the system and once the leak is found the mechanic can let you know of the exact cost to repair the leak and re-charge the system. If you desire that service please request an a/c system diagnostic – suspected refrigerant leak and the responding certified mechanic will get this taken care of for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you
Air conditioning smells bad when car enables autostop feature
ANSWER : Your vehicle is new enough that I couldn’t find much information on the air conditioning system. I’m guessing your vehicle probably has a dual scroll AC compressor in which one scroll is driven off the engine and the other is electric. In order to prevent lack of cooling at idle, this design is used in hybrids and vehicle with start/stop ability. So, the lack of cooling may be due to a problem with this system. The foul smell by be result of bacteria accumulating on the AC components. Replacing the cabin filter may help with this problem somewhat. I suggest you have a trained professional diagnose your vehicle firsthand to determine the exact cause of the smell.
Car will blow cold air but will not blow heat
ANSWER : The heater not working in some cases may be related to the overheating problem you are also having. This may be due to a faulty heater blower motor or potentially a bad heater core. As you may know, the heater core is a small radiator like unit that circulates the hot coolant from the engine through the heater core which then uses this warm coolant to heat the inside of the car with the help of the blower motor that blows the warm air through the vents inside the car. When the cooling system is not properly circulating coolant through the motor, this results in the warm coolant not being pumped through the heater core properly in order to warm the inside of the vehicle.
Engine overheating can be caused by a number of things such as low coolant levels, a faulty thermostat, or a failing coolant fan switch. As you may know the coolant fan switch helps to maintain the proper coolant temperature by turning on and off at specific temperature thresholds. When this switch is not working properly, this can cause the fans to come on intermittently, all the time or sometimes not at all. When this happens you will notice a temperature spike and drop occasionally as the fan comes on and off. When your thermostat is not working properly or is stuck closed, this will not allow the coolant to properly circulate through the engine, which may cause the engine temperature to fluctuate erratically or in some cases just remain hot. As mentioned above, this also restricts the warm coolant from flowing through the heater core which uses this to blow warm air into the cab of the vehicle. I would suggest having an expert from Your Mechanic come to your home to diagnose your cooling system.
everytime I turn my car on the ac starts to blow air even if I switch it off. it won’t blow cold air or heat.
ANSWER : Hi there. Based on your question and input, it looks like your AC control switches are damaged, causing the vents to activate even if the switch is not activated. This is sometimes an electrical problem, as it could be triggered by a damaged electrical relay. You might want to have a professional mechanic complete an AC is not working inspection, so they can determine what is causing this issue you’re experiencing and recommend the right repair.
My heat and air turns on without a problem but does not blow very hard (heat blows harder than air). Rattling noise.
ANSWER : The heater and the air conditioner both use the same blower motor. However, Nissan does have two separate fuses for the same unit. One of them can be blown. There are also resistors in the system that can fail. There are several electrical tests that can be done, but depending on the condition, it may be more practice to change the entire unit. Due to the age of your vehicle, and the Juke’s history of blower motor issues, it’s very likely a simple fuse issue. These can (for the most part) be visually inspected, and are cheap.
Will a missing air box resonator stop my car from going over 10mph?
ANSWER : Hi There,
The air box resonator missing should not impact the running condition of your vehicle at all. If the air box had cracks in it, this may have caused excess air to be injected into the intake system which may affect the reading of something called the mass air flow sensor which meters the air intake into the engine. When this is producing faulty readings or detects abnormal air intake, this may cause the jerking reactions you describe. The mass air flow sensor monitors air intake as it is mixed with fuel prior to being injected into the motor. This sensor relays vital information to the ECM which uses this to make adjustments to fuel supply to the motor. A dirty or faulty sensor can cause an imbalanced air/fuel load to be supplied to the motor which results in an over fueling or under fueling situation depending on the conditions. This type of inconsistent fuel supply to the motor may cause a hesitation, loss of power, a jerking reaction, potentially a bit of black exhaust smoke and typically a strong smell of fuel when this sensor is malfunctioning. I would suggest having a professional from Your Mechanic come to your home to diagnose and inspect your vehicle.
