Hi,

I had problems pushing my caravan through the emission this year as the PCM tripped P0601 code (posted a thread before). I replaced the PCM took the van for emission and the 6 categories on emission screen were - DTC not ready. I knew i had to drive a few miles but.. after approximately 50 miles upon return to the station I still had two categories as not ready - EGR system and EVAP system. The technician told me to drive for another 20 -30 mile so I did. Agan, came back and the same story.
The question I have is - how many miles do I need to drive after replacing the PCM? Also, if the EGR valve or EVAP solenoid or LDP pump is defective would that cause the PCM not to receive any signal and then report - not ready? I had nothing but a headache with this issue and already I'm two months past due on emission. I also have very erratic idle when the van starts in the morning. The RPM goes up and down for about 15 minutes. Once warmed up the van runs like a champ.
Is there any specific drive cycle I need to follow? I remember last year after replacing the PCM I only drove for about 50 miles or less before the emission was passed.
Your suggestions as always are greatly appreciated.
Thanks!

 

I found something interesting....

Chrysler Drive Cycle Information
All Monitor Drive Trace

Pre-Conditioning Requirements:
- MIL must be off
- Cold start (Note: cold start temperature is undefined)
Driving Procedure
1) Warm engine up for five minutes (must reach closed loop)
2) Drive (with steady throttle) at a speed between 40 and 60 mph for 8 minutes.
3) Stop and idle for 3 minutes.
4) Drive (with steady throttle) at a speed above 20 mph for 2 minutes.
5) Turn key off, leave off for ten minutes (to run O2 sensor heater monitor).
Note: Due to the limited preconditions provided with this drive trace, NCVECS recommends using the monitor
specific drive traces for Chrysler vehicles.

Catalyst Monitor Drive Trace

Pre-Conditioning Requirements:
- MIL must be off.
- No DTCs present.
- Fuel level is between 15% and 85% full.
- ECT above 70º F.
- Engine must have run at least 90 seconds
- Engine between 1,350 & 1,900 rpm.
Driving Procedure
1) Idle vehicle for five minutes (to reach closed loop operation).
2) Drive with a steady vehicle speed between 30 and 45 mph for 2 minutes.

EGR System Monitor Drive Trace - Vacuum controlled

Pre-Conditioning Requirements:
- MIL must be off.
Driving Procedure
1) Idle vehicle for five minutes (to reach closed loop operation).
2) Drive with a steady vehicle speed between 40 & 60 mph for 8 minutes.

EGR System Monitor Drive Trace - Electronic

Pre-Conditioning Requirements:
- MIL must be off.
- MAP must be between 0-60 KPa.
- Engine speed between 500-850 rpm.
- ECT is above 180º F (90º C).
- No misfire temporary (pending) or matured fault present.
- A/C clutch, PS Switch and Cooling fans do not change state (turn off).
Driving Procedure
1) Idle vehicle for five (5) minutes (to reach closed loop operation).
2) Drive with a steady vehicle speed between 40 & 60 mph for 2 minutes.
3) Idle vehicle for three (3) minutes.
Note: This monitor evaluates EGR flow based on a change of engine roughness (idle stability).
Conditions causing un-stable idle will prevent this monitor from running.

Evaporative System Monitor Drive Trace

Trace 1: Standard Type
Pre-Conditioning Requirements:
- MIL must be off.
- No Evaporative DTCs present.
- Fuel level is between ½ and full.
(Note: monitor may still run with tank fill between 15% and 85%).
Driving Procedure
1) Idle vehicle for five minutes (to reach closed loop operation).
2) Drive with a steady vehicle speed between 30 and 45 mph for 2 minutes.

Trace 2: Leak Detection Pump

Pre-Conditioning Requirements:
- MIL must be off.
- No Evaporative DTCs present.
- Fuel level is between 30 & 85 % full.
Driving Procedure
1) Cold soak vehicle, start and idle vehicle for 4 minutes.
2) Drive in-town (stop and go) for 5 minutes, using smooth accelerations and decelerations.
3) Stop and idle vehicle for 4 minutes.
O2 Sensor Monitor Drive Trace
Pre-Conditioning Requirements:
- MIL must be off.
Driving Procedure
1) Idle vehicle for five minutes (to reach closed loop operation).
2) Drive with a steady vehicle speed above 25 mph for 2 minutes.
3) Stop and idle for 30 seconds.
4) Smoothly accelerate to a speed between 30 and 40 mph.
5) Repeat steps 3 & 4 five (5) times.

O2 Sensor Heater Monitor Drive Trace

Pre-Conditioning Requirements:
- MIL must be off.
Driving Procedure
1) Idle vehicle for five minutes (to reach closed loop operation).
2) Shut engine off and leave vehicle off for ten minutes.