Mechanics

P0430 CODE

1997 Mercury Marquis • V8 2WD Automatic • 118,525 miles

Ok ok, let me first start by saying many of you have been helpful in the past and hopefully will come thru for me again.I have a 97 grand marquis that has over 115,000 miles on it. Recently, I had a problem with check engine light on for the past yr and half. Finally broke my last nerve with it on and went out and purchased a scan tool. Retrieved codes p0171 and p0174. Found out what they were. Repaired the problem. Found tiny hole in egr boot. Replaced as req. Drove car for at least 150 miles. Rechecked obd-2 system and had monitors cat and evap "not ready"yet for testing. Ran car thru inspection and it passed. Cars drivability is fine. No engine light or anything until today, while driving, all of the sudden the light comes on. Return home from running errands and hook up scan tool. Pull up code p0430.I know what code means. Here are the parameters the engine was at when the light came on: fuel sys.1, closed, fuel sys 2 n/a, calc load 32.9%, ect at 181, stft b1 at -2.3, ltft b1 at 22.7%, stft b2 at 0.0%, ltft b2 at -100%. I hope this helps someone help me understand whats going on. Really don't feel like replacing a converter.O2 sensor I maybe able to. Please help. Thanx in advance, dano
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Dano2448
November 24, 2010.



You failed to mention after the repairs, that you properly went through drive cycle? Just in case I am sending you the drive cycle, clear the codes and retry. If you never let the gas tank dropped below a 1/4 the EVAP will not actuate and set a code. Now about your catalytic converter, how much exhaust pressure do you have? Can you easily put your hand over the tail pipe, and stop the exhaust?

OBD-II DRIVE CYCLE
NOTE: The IAT PID must be between 50-100° F (10-38°C) during the OBD II drive cycle to enter into all the OBD II monitors. The FLI PID must be between 15% and 85% at all times.

Drive in stop-and-go traffic with at least 4 idle periods (30 seconds each) while observing the status of the OBD II monitor on the scan tool. If the Exhaust Gas Recirculation (EGR), Heated Oxygen sensor (HO2S), Evaporative Emission (EVAP), Secondary Air (AIR) (if applicable) or catalyst efficiency monitor have not completed, drive on the highway at a constant speed over 40 MPH (64 km/hr), not to exceed 65 MPH (104 km/hr) for up to 15 minutes. Heavy accelerations, sudden decelerations and wide open throttles are not recommended. If the scan tool sends out a 3 pulse beep at any time, the OBD II drive cycle has completed.
NOTE: Vehicles equipped with the EVAP purge flow system or EVAP vapor management flow system monitor do not require EVAP monitor completion to clear the DTC P1000. See appropriate monitor under ON BOARD DIAGNOSTIC-II MONITOR. If the Exhaust Gas Recirculation (EGR), Heated Oxygen Sensor (HO2S), Evaporative Emission (EVAP), Secondary Air Injection (AIR) (if applicable) or catalyst efficiency monitor has not completed, perform the corresponding monitor verification drive cycle in this section.

Bring the vehicle to a stop and retrieve continuous memory DTCs to verify the DTC P1000 has been erased. See QUICK TEST.

EGR MONITOR REPAIR VERIFICATION DRIVE CYCLE
NOTE: Ambient air temperature or IAT PID must read a minimum of 32°F (0°C) to initiate the EGR monitor.

Refer to and complete the vehicle check and preparation before initiating the following repair verification steps. See VEHICLE CHECK/PREPARATION.
Start the engine and drive the vehicle for 6 minutes: Drive in stop-and-go traffic for 5 minutes with at least 2 idle periods.
Accelerate to 45 MPH (72 km/h) at more than 1/2 throttle (35 MPH [56 km/h] on Escort/Tracer). Maintain speed for one minute.
Rerun quick test. See QUICK TEST.

EVAP RUNNING LOSS MONITOR SYSTEM REPAIR VERIFICATION DRIVE CYCLE
Perform the preparation for OBD II drive cycle section. See VEHICLE PREPARATION FOR OBD-II OR MONITOR REPAIR VERIFICATION DRIVE CYCLE under DRIVE CYCLES.
With the scan tool, verify the FTP V PID reads between 2.4 and 2.8 volts with the gas cap removed. Reinstall gas cap.
With the scan tool, view the OBD II monitors through the ON-BOARD SYSTEM READINESS menu.
Drive the vehicle at a constant speed between 35 MPH (56 km/hr) and 65 MPH (104 km/hr) with throttle as steady as possible. Observe the HO2S monitor on the scan tool until it completes, or refer to FUEL MONITOR OR HO2S MONITOR REPAIR VERIFICATION DRIVE CYCLE.
Bring the vehicle to a stop and access the following PIDs with the scan tool: IAT, FLI, FTP, V, EVAPPDC, EVAPCV.
Verify the following EVAP monitor entry condition: IAT between 50-100°F (10-38°C).
Drive the vehicle on the highway with a constant speed over 64 km/hr (40 MPH) with throttle as steady as possible. During this time, verify the following additional EVAP monitor entry conditions using the FLI and FTPV PIDs: FLI stable +/- 5% between the limits of 15% and 85% tank fill.
FTP V stable within +/- 0.1 volt.
Prior to running the EVAP monitor, when the EVAPPDC PID is less than 75%, the canister vent solenoid is open and the system is unsealed. To initiate the EVAP monitor, the EVAPPDC PID must increase to at least 75%. At this time, the EVAPCV PID will then display 100% (canister vent solenoid closed to seal the system and the monitor will begin to run. Continue to drive at steady throttle with light steering until the EVAPCV PID displays 0% (canister vent solenoid open, system unsealed). If this step does not occur as described, proceed to the following note, otherwise proceed to next step.
NOTE: During the drive cycle or hot ambient temperatures, fuel vapor (from the canister and/or tank) may keep the test from starting. The following be observed on the scan tool when either: The EVAPPDC PID never reaches 75% with stable FLI and FTP PID readings.
The EVAPCV PID never goes to 100% (canister vent never closes) when the EVAPPDC PID is above the 75% minimum to start the test.

Bring vehicle to a stop.
With the scan tool, view the EVAP monitor for completion through the On-Board System Readiness Menu. Repeat 7 if the EVAP monitor is not complete.

Dr Loot
Nov 26, 2010.