Cold Start Injector: Testing and Inspection

1. Disconnect cold start valve electrical connector and check resistance between terminals of valve.

RESISTANCE: 3 - 5 ohms (@ 68°F/20°C)

If resistance is not within specification, replace cold start injector.

Cold Start Injector:

2. Remove valve from throttle body, leaving fuel line connected.

3. To avoid fuel spraying in your face, wrap a piece of clear plastic around the injector nozzle in the shape of a cone. Secure with wire or nylon tie.

4. Energize fuel pump by jumping between terminals of the fuel pump test connector (yellow 2-pin connector near air flow meter), and turning the ignition "ON".

5. Hold injector over suitable container, to collect fuel sprayed from the nozzle, and check injector operation, by momentarily applying power and ground while observing spray pattern.

^ A finely atomized cone shaped mist of fuel should spray from injector nozzle.

WARNING: Fire hazard. Use appropriate connectors and long jumper wires or remote switch, so as not to create any sparks near the injectors or the container of fuel. The mist of fuel sprayed from the injector can ignite very easily.

6. Dry off injector tips with a clean cloth and check for fuel dripping from injectors. After a minute or so, some wetting or even a drop of fuel seeping from an injector nozzle is acceptable. More than one drip per minute, with the fuel pump running, is unacceptable.

Leaking injectors and injectors with poor spray patterns can sometimes be cleaned with a chemical fuel system cleaner and re-used. Use a cleaner designed for fuel injectors. Also some gasolines contain a cleaning additive for fuel injection systems. If clogged or leaking injectors are suspected, switching to one of these gasoline brands may help.

If cleaning does not restore normal injector operation, replace the injector(s).

NOTE: Before opening any fuel system connections, always relieve fuel system pressure by starting engine with fuel pump relay (circuit open relay) disconnected and let run until engine dies, then slowly and carefully remove hose on outlet side of fuel filter. Cover with a clean rag while removing hose, to avoid spraying fuel in your face. On the 929 DOHC V-6 engine, fuel system pressure can also be relieved by gradually and carefully loosening the banjo bolt on the cold start valve (on top of the throttle body). Cover with a clean rag when doing so, to avoid spraying fuel.