What does the exhaust light mean?

In many vehicles, an exhaust light (or emissions light) is used to warn the driver of exhaust-related problems. This allows the driver to take action before more damage occurs. When an irregularity is detected in the exhaust system, the exhaust light will turn on, and a fault code will be saved to your car’s computer. This will allow for mechanics to quickly diagnose the problem using appropriate scan tools.

Exhaust lights vary in different vehicles, with some showing a catalytic converter icon, whereas others show a “check exhaust” message. In vehicles without an exhaust/emissions light, the check engine light is generally used to signal the user of exhaust-related problems.


Common causes of exhaust light:

If the exhaust light is on, it could point to the following symptoms:

Damaged catalytic converter – The catalytic converter reduces emissions produced by your vehicle. If it fails or malfunctions, the exhaust light may turn on. A damaged catalytic converter can let more harmful green house gas emissions into the atmosphere than normal, causes damaging pollution.

Damaged exhaust manifold – The exhaust manifold collects the exhaust emissions from all of your vehicle’s cylinders. If it is damaged, it can leak exhaust emissions into the rest of your vehicle, potentially putting toxic / lethal exhaust gases in the vehicles cabin for you and your passengers to breath in. In extreme cases hot exhaust gases can damage plastic and wiring close by.

Faulty sensors – Your engine uses several different sensors to detect air/fuel levels and exhaust temperature. If one of these sensors stops working, the air/fuel mixture will be different to normal. This causes the exhaust to behave differently.

Tips on diagnosing exhaust problems >


Symptoms of exhaust problems:

As well as an illuminated exhaust warning light, the following symptoms can point to a problem in your car’s exhaust:

  • Decreased fuel efficiency
  • Burning smell from the engine
  • Reduced power and acceleration
  • The exhaust produces lots of black smoke (fuel too rich)
  • Loud noise from exhaust system indicating a leaking exhaust


How important is an exhaust inspection?

The longer the exhaust remains damaged, the more problems can occur. A damaged/leaking exhaust can put toxic / lethal exhaust gases in the vehicles cabin for you and your passengers to breath in, damage surrounding components, increase fuel consumption, pump out increased green house gases, and cause your vehicle to fail a Warrant of Fitness / WOF.

For these reasons, we recommend that you get your vehicle’s exhaust dash warning light diagnosed as quickly as possible.


Exhaust Light Diagnostics & Inspection in Hamilton

At Grimmer Motors, we have a variety of car diagnostic scan tools. This allows for us to quickly and correctly identify faults in your cars exhaust and engine. Once the faults are identified, we can provide you with a quality fix that you can rely on.

For fast, cost effective exhaust light fault code reading and diagnostics in Hamilton, contact Grimmer Motors today!


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