Circuit Description

WARNING: This page is about a different car, the 2000 Isuzu Hombre. However, it is still accessible from the selected car via links, so may be relevant.

Powertrain Control Module (PCM) internal circuitry can identify if vehicle fuel system is capable of supplying adequate amounts of fuel during heavy acceleration (power enrichment). When a power enrichment mode of operation is requested, PCM will allow additional fuel to be provided to engine. If PCM does not detect a rich exhaust, a DTC P1171 will set.

Conditions for setting this DTC are:

O2S 1 voltage is less than 300 mV for 5 seconds.
O2S 1 is operating in closed loop.
Fuel injector BPW is greater than zero.
Fuel delivery system is in power enrichment mode.
ECT is greater than 68°F (20°C).
Engine has been running for longer than 20 seconds.