Good Afteroon Everyone,

I have a 2011 Lancer GTS with 63k miles on it and have been suffering from an exhaust smell in the cabin that has lead to me becoming light headed multiple times. I have had three different Mitsubishi dealerships search for the past 3 years and none have had any luck figuring it out, only recommending the odor bomb. I live in Arizona, so you can imagine it gets hot outside, this problem seems to only occur when the temp is over 100 degrees outside and after the car has ran for about 20 minutes. You can smell the exhaust in both the cabin and outside the car. I have contacted Mitsubishi as well as my dealership has asked Mitsubishi for help and all we both get is "good luck, but we aren't helping." My dealership has stated that many people in this area have been experiencing this and they have started collecting vin numbers of the affected cars, however I don't know where this will go as Mitsubishi says they are not responsible for any of this. I have also been told that even though this is now becoming a bigger problem in this area and I have been having my vehicle looked at for 3+ years for this issue that since it is now out of the 60k mile warranty that Mitsubishi will not even consider looking at it anymore. I am hoping someone else here has seen this or has some suggestions on what to do.

 

When does the exhaust smell start?
when the car is idle?
when turning it on initially?
while driving and accelerating?
when coming to a stop?
With AC and air off or on?
Windows closed or open?
I ask because depending on when can actually help you find out what and where the smell is coming from.

Do you have a odb2 reader diagnostic tool? sometimes you can get a good scan tool for this. With fumes its not good to leave it as is for you or your family. the price to pay later is much worse. even if you have to invest a $100 bucks on your own scan tool. I personally use BlueDriver Professional OBDII scan tool to find the codes and logs for my outlander. This might be something that is even covered under the warranty if your car is just under the 7 year mark when purchased.

 

Luar,

The exhaust smell usually starts about 20 to 30 minutes after driving when the outside temperature is over 100 degrees. The smell is definitely stronger when the car is idle at a red light or when I park, however you can smell it both when stopped and driving. When initially turning the car on I don't tend to notice the smell. Typically the AC is on, however I have tested both on and off in the past with no difference. I almost always keep my windows closed, except when I need to vent the car due to the smell.

I do not currently have a diagnostic tool, but was considering getting one. I will take a look at a few and purchase one this week.

I am the original owner of the car and purchased new. The issue I am running into is that no one can seem to pinpoint the issue and no codes tend to come up on diagnostic tools. The car also has no problems passing emissions, however emissions is typically done in January, so the ambient temperature is much lower. Being that this is more common when the outside temperature is over 100, my suspicion is that it has something to do with expansion and contraction of something in the exhaust system. I have been reporting this issue for the past 3 years, but still no one can seem to figure it out. I wish I had the room, tools and knowledge to get in there myself and try to diagnose it, however I currently do not. It is worth noting that the local dealership has stated that this summer they have seen many new local reports of this issue and have not had luck in figuring out the solution for any of the cases. The dealership is also the only Mitsubishi dealership in my area and only opened a year or so ago, before then we had to drive 90+ miles to another dealership for servicing, etc. They also noted that this issue is starting to popup in other cars, ie. Jeep and Ford.

 

thanks for the description and just in general sadly because of technology most auto shops and dealerships only say something is wrong with your car when there are error codes. however, an error code in a car will only display when it hits a large ratio trigger point and not necessarily when there is a problem with a car. a cars idle, rpm, air intake, temp and other variables can help determine issues way before they start and of course common sense of our body telling us there is a bad smell, the car shakes or does not accelerate correctly.

some simple things to check:
1. small holes in the exhaust pipe, tailpipe and muffler can cause this only when accelerating or at high temperatures because of the over expansion of heat

2. any gas or oil drips or perhaps gas cap not sealed tight (i dont know how many times ive seen a car with this that even i overlook, sometimes the simple stuff is the most overlooked)

3. how is the fuel performance? has it reduced over time or get worse in summer or heat?

4. prolonged overheating can cause catalytic converter leaks which are not picked up by error odb2 tools if they emission or temp is still within range. the underlying cause here is often fouled or misfiring spark plugs, or a burned exhaust valve that leaks compression and allows unburned fuel to pass through the combustion chamber into the exhaust

5. a bad fuel pressure regulator can also cause problems with fuel mixture. when you burn excess gas, this can increase the presence of gas fumes in your exhaust. if exhaust enters your ventilation system through a leak, the interior may also begin to smell like gas fumes. other signs of a failing fuel pressure regulator include decreased power and lower than normal fuel efficiency of your car.

overall causes of fuel smells in car as described when driving in heat also injector leak,
fuel tank leak, fuel line leak, faulty canister, faulty gas cap, catalytic converter

a portable fuel detector may help. sometimes you can find a new or used on at amazon or ebay

 

When does the exhaust smell start?