After getting rid of the p0400 code my "rv meter" worked fine again.
There is a diagnostic mode on the rv meter....i mistakenly pressed adj instead of disp button while trying to reset it.

 

How to you access the Diagnostic mode?

 

Same procedure as resetting the rv meter but press adj instead of disp.

 

After about 200 miles of driving the p0400 appeared again. Good thing I don't have work tomorrow....i bet there's a chunk of carbon that loosened the first time I cleaned it and now found it's way in one of the vacuum lines or ports.

 

The manual I have doesn't show a P0400. The closest thing is a P0401.

The funny thing is that you've mentioned 3 problems : Code P0125, Code P0400, and an incorrect DTE on the RV Meter. The thing all three of these have in common is signal processing done in the PCM (Powertrain Control Module).

For what it's worth here is a copy and paste of the description for P0401 (Exhaust Gas Recirculation Flow Insufficient Detected) :

TECHNICAL DESCRIPTION
• When the EGR valve (stepper motor) is actuated from the fully closed position toward the open position while the engine is running, EGR gas flows.
• The PCM checks how the EGR gas flow signal changes.
DTC SET CONDITIONS

Check Conditions
• At least 20 seconds have passed since the last monitor was complete.
• Engine coolant temperature is higher than 76°C (169°F).
• Engine speed is at between 910 and 1,650 r/min.
• Intake air temperature is higher than 0°C (32°F).
• Barometric pressure is higher than 76 kPa (11 psi).
• Vehicle speed is 30 km/h (18.7 mph) or more.
• At least 90 seconds have passed since manifold differential pressure sensor output voltage fluctuated 1.5 volts or more.
• The throttle valve is closed.
• Volumetric efficiency is lower than 28 percent.
• The PCM monitors for this condition for 3 cycles of 2 seconds each during the drive cycle.

Judgement Criteria
• When the EGR valve opens to the prescribed opening, when intake manifold pressure fluctuation width is lower than 2.6 kPa (0.37 psi).
TROUBLESHOOTING HINTS (The most likely causes for this code to be set are: )
• Dirtiness of the EGR valve and EGR passage.
• EGR valve (stopper motor) failed.
• Open or shorted EGR valve (stopper motor) circuit, or loose connector.
• Manifold differential pressure sensor failed.
• PCM failed.


Hope this helps.

 

Hi montecrazy,the p0125 was due to a faulty thermostat that was stuck open. When cruising on the freeway my coolant temp goes way down so it triggers the p0125 code.
P0400 is exhaust gas recirculation flow malfunction..
I'll review your post and see what i come up with. Thanks.

 

After checking all hoses and ports,no blockage was found. Pinched the vacuum line from the throttle body to the egr solenoid and engine stumbles,checked egr valve and engine stumbles when it is activated. Removed egr solenoid and tested it for operation and it clicks everytime power is introduced...which made me think that maybe it is the PCM that is faulty. Attached egr solenoid to the vacuum lines but not the connector and turned it on manually,there is a click but no stumble. Got a new egr solenoid and attached it the same way,engine stumbles when I turned it on manually. Installed the new egr solenoid and plugged in the connector and took it for a test drive. A few miles after driving, the egr system test was complete without triggering another code. So hopefully that finally fixed my p0400 code.

 

montymecrazy,i noticed that the mileage reading on my rv meter isn't moving again as I drive...i did reset it a couple of times and even removed the battery but still no movement. So maybe the pcm isn't communicating well with the rv meter. But I can live with that,will just put display on a different screen...climate control display maybe. Hahaha.
Remember the diagnostics screen that appears if you press adj instead of disp...in one of the screens it says there was error 001 with ecu com. Will take a pic of it later and post it here.

 

My Monty has gremlins too. Good luck and thanks for the updates.

 

Removed the rv meter yesterday from the dash,unplugged all connectors and plugged them again...working fine for two days now. Keeping my fingers crossed.