Check engine lights on Suzuki vehicles such as Swift, SX4, Jimmy, XL7, etc., may come on due to something as simple as a loose gas cap, but it can also indicate a more serious engine problem such as an engine misfire.
What does the check engine light mean?
If your Suzuki check engine light stays on all the time, it means the On-Board Diagnostic system of your vehicle has detected a problem with the engine operation, emission system, or transmission.
Unlike other warning lights, a whole range of faults can trigger this warning, so it is hard to tell what could be the problem without an OBD-II scanner.
For instance, a faulty downstream O2 sensor is not something that would be harmful in the short-term. On the other hand, you might have a faulty MAF sensor or CPS sensor, causing other damage if ignored for a long time.
Common symptoms that you may notice:
- Suzuki check engine light flashing.
- Engine running rough
- Engine juddering
- Lack of power
- Poor throttle response
- Smoke from the exhaust
- Cruise control and check engine light come on.
Any of the described symptoms indicate that your engine is not running right.
How to diagnose Suzuki check engine light?
Although there are some steps you can try, like checking the gas cap or looking for anything loose under a hood, you will usually be pretty much in the dark without reading the codes.
Follow the instructions below to learn how to use an OBD2 diagnostic scanner to read the codes via the OBD2 port located under the dashboard.
- Locate the diagnostic port under the dashboard—plugin your scanner.
- Turn on the ignition but do not start the engine. Allow the scanner to turn on.
- Select Diagnose then Suzuki model. If using a generic scanner, select OBD-II.
- Scroll down to Read Codes and press OK.
An OBD2 scanner is a diagnostic tool that you use to get the stored engine trouble codes and read engine running parameters.
They come in different shapes and sizes, ranging from simple Bluetooth readers that connect to your smartphone to dedicated handheld devices.
Still, they all connect to the OBD2 port that is usually located under the steering wheel.
Once you retrieve the codes, research them online to understand better what they mean and possible causes.
Common problems that trigger check engine light on a Suzuki
EGR related issues are something that seems to strike V6 engines more often than 4 cylinder ones.
In most cases, the root of the problem will be in the carbon buildup, so try cleaning the EGR valve. There is various EGR cleaner spray for this job. Replacing the EGR valve is only needed if it is jammed or does not work at all.
Code: P0401 (EGR insufficient flow)
Mass Air Flow Sensor
Suzuki engines seem to have more than average rich running problems. The rich condition will cause a negative fuel trim in both short and long term fuel trims.
Also, to check engine light, look for black smoke from engine exhaust and smell of unburnt fuel. This can be caused either by a dirty or faulty mass airflow sensor (MAF), stuck open fuel injector, or engine running too cold.
Don't use anything else than MAF cleaner fluid for removing dirt buildup.
Codes P0172 and P0175
If you drive a higher-mileage Suzuki, you will likely encounter an emission control that caused check engine light.
Although this will be signaled as a catalytic converter low efficiency, you may have a faulty downstream O2 sensor. Make sure to rule this out before changing a more expensive catalytic converter.
Codes: P0410 and P0420 (Catalyst Efficiency Below Threshold)
Various EVAP related leaks can trigger a check engine light. In most cases, it is accompanied by a strong gas odor.
Check if the fuel tank cap is loose or missing. Next, a purge control valve might be leaking or broken.
Lastly, check all fuel and EVAP lines for leaks, as they can have cracks.
Code: P0449 (EVAP purge valve)
Idle Air Control Valve (IACV) is another common failure point.
In addition to a check engine light, you might experience rough idle and stalling when coming to a stop.
Sometimes this will be caused by a carbon buildup, so you can try cleaning the IACV with carb cleaner.
If that does not help, replace the valve.
Code: P0505 (Idle Air Control Valve)
If your Suzuki has an automatic gearbox, it may trigger a check engine light. If there are no other apparent symptoms, this can be caused by dirty or low oil level or a faulty TCC solenoid valve.
Codes: P0741 (Torque converter clutch - circuit performance)
On some models, like Forenza or Reno, you might be experiencing harsh downshifts from 4th to 3rd gear, followed by a check engine light.
In most cases, this will be caused by a fault in the Transmission Control Module (TCM) software logic.
In most cases, TCM will need to be reprogrammed by a dealer. As this is a manufacturer's fault, it should be charge-free.
Why is my Suzuki check engine light flashing on and off?
While a whole range of problems can cause a solid check engine light, if your Suzuki check engine light is flashing, it signals a misfire.
Common failures that cause a misfire include:
- a bad spark plug,
- ignition coil,
- catalytic converter,
- mass airflow sensor.
Do not drive if the check engine light is flashing.
If your engine runs rough and shakes, unburned fuel is getting into the exhaust, causing damage to the catalytic converter.