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Diagnostic Aids

WARNING: This page is about a different car, the 1994 Cadillac Fleetwood. However, it is still accessible from the selected car via links, so may be relevant.

If an injector is disconnected and then reconnected while engine is running, injector driver is disabled for a predetermined time and Code 18 will set. When driver is disabled, an engine misfire will be evident.

Fig 1: Code 18 Schematic (Fleetwood) Injector Circuit
G94F35001
Fig 2: Code 18 Flow Chart (Fleetwood) Injector Circuit
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