Troubleshooting Saab Check Engine Light

All 1996 and newer Sabb vehicles including 9-3, 9-5, 900, 92x Aero (which is identical to Subaru WRX) have a small warning light on the dashboard known as the check engine light. 

In this guide, we will take a look at Saab check engine light, what it means, what causes it to flash and how to diagnose it yourself. 

What does the check engine light mean? 

When your Saab check engine light stays on it means that the On Board Diagnostic (OBD) computer has detected a malfunction. The cause could be due to an engine problem, fuel system leak or even an indication of a transmission issue. 

Since a fault code will be stored in your Saab's OBD computer you can use an OBD-II scanner to read those codes. 

Symptoms

When your Saab check engine light comes on you may notice: 

• Engine running rough 
• Engine shaking or juddering
• Lack of power
• Poor throttle response
• Check engine light flashing
• Smoke from the exhaust

In some cases, you may not notice any performance issues at all. As would be the case if you forget to tighten the gas cap. 

Saab Check Engine Light Flashing

Pay extra attention if Saab check engine light is flashing.

If your Saab CEL is flashing on and off intermittently indicates a misfire. Fuel is not getting burned in the cylinder. 

The problems usually is due to: 

• bad spark plugs
• ignition coils
• catalytic converter
• mass air flow sensor

We don't recommend to drive a Saab if the check engine light is flashing to avoid causing more damage to the engine and catalytic converter. 

Common Causes

Fuel Injector

Saab turbocharged engines can have problems with fuel injectors.

This will cause excessive smoke from the exhaust on startup and sometimes while driving, combined with rough running and hesitation.

The root cause for this is a dirty fuel, which causes build-up on the injectors and poor spray pattern.

The best solution is to have injectors cleaned by a specialist.

Related Fault Codes: P0245 and P0201 to P0201

Crankshaft Position Sensor

Crankshaft Position Sensor is a known failure point, as they sometimes endure extreme temperatures. In most cases, they will start failing gradually, initially causing only occasional running problems. Usual, telltale signs are sporadic crank-but-no-start situations.

Codes: P0336 or P0337 

Spark Plugs

Random misfire is another problem you might encounter when you have worn out spark plugs.

In addition to flashing 'check engine' light, you may experience juddering and hesitation.

Have these issues checked without any delay, as it can easily cause additional damage. 

Related Fault Codes: P0300 and P0301 to P0304

Mass Air Flow Sensor

A dirty MAF sensor will give false air-flow readings. This can upset the air-fuel mixture, and cause the engine to run rough and stall.

Luckily, this can be easily cleaned, but don’t use anything else than MAF cleaner fluid for removing dirt buildup.

MAF sensor could be the issue if you have an intermittent check engine light problem. MAF sensor may function fine when the engine is cold then start to malfunction once the engine warms up. 

Code: P0102 MAF sensor

Engine Temperature Sensor

A coolant temperature sensor can go bad with time, causing the engine to run rich and preventing it from going into 'closed-loop' mode.

Although not causing any immediate problems, this will impact the gas mileage and can damage the catalytic converter in the long run.

Code: P0117

Anti-brake System Failure

In some cases, it is possible to have a ‘check engine’ light in combination with ABS/TCS warning light.

This issue is usually caused by an ABS/TCS unit internal problem, causing a communication error.  

The only real solution for this is to remove the ABS/TCS control unit from the car and send it to a specialist for repair.  

Throttle Body

Many Saab models from 2000-2010 have running issues caused by a faulty throttle body.

Typical symptoms are stalling and poor throttle response. In addition to ‘check engine’ light, your car even might go into ‘limp home’ mode, which limits the performance and speed.

The problem lies within the potentiometer that gets damaged by corrosion and dirt. Code: P2135 

How to diagnose Saab Check Engine Light

With a 'check engine' light on, the first thing you need to find out is what caused it. You can either take your car to the workshop for a full diagnosis or read the fault codes with an OBD-II scanner.

These devices come at all shapes, sizes, and prices to choose from. The choices range from something simple as a Bluetooth OBD adapter that connects to an application on your smartphone, over dedicated hand-held scan tools to powerful diagnostic tools.

With any of them, you will be able to get the stored engine trouble codes and read engine running parameters.