P0153

Tests 338 - 342:

Tests 343 - 345:

SYMPTOM
P-0153 2/1 O2S SLOW RESPONSE

WHEN MONITORED
With engine temp > 147 degrees F, after reaching a vehicle speed of 10 mph, and the throttle remaining open (off idle) for two minutes, bring the vehicle to a stop and allow the engine to idle with the transmission in drive (auto) or in neutral (manual).

SET CONDITION
The oxygen sensor signal voltage is switching from below 0.27 volts to above 0.62 volts and back fewer times than required.

POSSIBLE CAUSES
- Engine mechanical problem
- 2/1 O2 sensor ground ckt high resistance
- 2/1 O2 sensor ground ckt poor connection
- 2/1 O2 sensor signal ckt high resistance
- 2/1 O2 sensor signal ckt poor connection
- 2/1 O2 sensor slow response
- Exhaust leak
- 2/1 O2 sensor slow response does not reoccur