Testing and Cleaning the Cold Start Injector Valve

An essential for any fuel injected car, the cold start valve shoots extra fuel into the fuel injection system to assist in starting the car when the engine hasn't ran in several hours is at a cold temperature. 

Per the Saab factory workshop manual, the injector functions when the engine temperature is less than 113 degrees F or 45 degrees C. 

Refurbished injectors are easily sourced on eBay, as this is a Bosch part (as part of the K-Jet system), so they were used commonly on Audis and Porsches. They are rather expensive, so try cleaning your injector before you buy a new one.

The common culprit is difficulty starting when you, say, haven't driven your car in a day or so. If you experience this when starting a vehicle with mechanical fuel injection, like any K-Jet car, then it's probably time to clean the injector valve, or at least test it to see if it's functioning.

Locate the injector on top of the throttle body. It should be sticking upward on a slant, with a blue plug towards the top. 

Before we remove anything, test the injector by undoing the two retaining screws at the bottom of the valve. Place the injector end of the valve in a cup/container, then turn the car over. If it squirts fuel into the container, then it's functioning properly, but maybe not sending enough fuel to the injection system.

To further test it, place the fuel line and banjo o-ring it's connected to into a container. Then turn the car over on a cold engine and see if it squirts fuel inside the container. If there's a good stream of fuel being sent in, then you most likely have a dirty injector that is clogging up fuel flow into the injection system. 

Removal is simple. 

1. Undo the two retaining screws. 
2. Disconnect the plug connecting to the blue port on top of the valve. 
3. Undo the two small hoses that connect below the hose in a Y shape.
4. Using a 13mm, undo the banjo bolt leading to the top of the valve.
5. Remove the injector from its housing.

Use some carbon throttle body cleaner to clean the valve off. Shoot it down through the valve, and allow ample time to dry before reinstalling. If you have access, use a 12V power source to open the valve to get better access when spraying the cleaner inside. 

Installation is carried out in reverse order.

If you haven't started your car yet, turn the car over on a cold engine to see if it starts better. If the engine is warm, wait a few hours or day. If it continues to have trouble starting, investigate further, or bring it to your Saab specialist. You can have these parts ultrasonically cleaned as well.