Hyundai GENESIS COUPE BK 2010 Manual page 828

■ Check injector for normal operation
1. Start engine.
2. Check its RPM decrease when doing the injector's actuation test.
3. Is there any cylinder with no change in RPM or only a small change in RPM?
▶ Replace injector, and go to "Verification of Vehicle Repair" procedure.
▶ Clear DTC and Test-drive under enable conditions above-mentioned. After the test, If this
DTC is set, go to "Inspection & Repair" procedure. If not, troubleshooting is completed.
Verification of Vehicle Repair
After a repair, it is essential to verify that the fault has been corrected.
1. Connect GDS and select "DTC" button.
2. Press "DTC Status" button and confirm that "DTC Readiness Flag" indicates "Completed". If not, drive the vehicle
within conditions noted in the freeze frame data or enable conditions.
3. Read "DTC Status" parameter.
4. Is parameter displayed "History(Not Present) fault" ?
▶ System performing to specification at this time. Clear the DTC.
▶ Go to the applicable troubleshooting procedure.
Fuel System > Engine Control System > P0172 System too Rich (Bank 1)
General Description
In order to provide the best possible combination of drivability, fuel economy and emission control, the PCM uses a
closed loop air/fuel metering system. The PCM monitors the HO2S signal voltage and adjusts fuel delivery based it in
closed loop fuel control. Changes in fuel delivery will be indicated by the long-term and the short-term fuel trim values.
The ideal fuel trim value is around 0%. The PCM will add fuel when the HO2S signal is indicating a lean condition.
Additional fuel is indicated by fuel trim values that are above 0%. The PCM will reduce fuel when the HO2S signal is
indicating a rich condition. Reduction in fuel is indicated by fuel trim values that are below 0%. The DTC relevant to fuel
trim will be set when the amount reaches excessive levels because of a lean or rich condition.
DTC Description
Checking the fuel trime value under detecting condition, if its average exceeds the limit over certain period, PCM sets
P0172. MIL(Malfunction Indication Lamp) turns on when the malfunction lasts till consecutive 2 driving cycle.
DTC Detecting Condition
Item
DTC Strategy
Enable Conditions
Detecting Condition
• Monitor the fuel trim value
• Engine warm-up sufficiently
• Drive at a steady speed over 5 minutes ( Vehicle
speed ≤ 130km/h)
Possible Cause