Faulty EGR value may cause engine hesitation under light acceleration. In this case, you need to hook up a Honda HIM HDS (Honda Diagnostic System) kit to get the fault code cleared. If EGR value is faulty, replace it with a new EGR value. Here is an step by step instruction on reset Honda Pilot 2004 EGR value with HDS.
The same procedure applied to 1999 -2003 Odyssey and 2003 up Pilot.
Honda HDS HIM diagnostic tool with double board with V3.15.020 software
A laptop running Win XP home
A new EGR value
Connect Honda HIM with vehicle via OBD socket
Turn ignition ON, run HDS Honda software
At the screen prompts enter the VIN and the odometer reading, and then verify the correct date/time
Select “Mode” Menu
Select “Honda Systems”
Select “PGM F1” from “System Selection” Menu program
Select “Snapshot” from “Mode” Menu
Select the “Fast Sampling” button from the “Trigger Type” menu
Select these parameters: Engine speed, VSS, ECT sensor, Map sensor, TP sensor EGR-L-Command and EGR LIFT form the High Speed screen. Then press “Green Check” button on the left.
Select “Manual” when the “Trigger Type” menu is displayed, select Record Time for 30 seconds and move the trigger point to the middle. Then select the “Blue Check” button. Check that the defaulted trigger point is in the middle.
Run a test driver of the vehicle with the engine completely warm-up. Drive the vehicle between 40 and 55 mph on a smooth road surface. Apply light throttle with the transmission in 5th gear. If hesitation is felt, select the “Snapshot Manual Trigger” button.
NOTE: The snapshot should be done with two people so that one person can driver and the other can operate the honda hds software.
When the best-drive is complete, the Snapshot dialog box is displayed, select “Yes”, then select “OK”, at this point, the snapshot is stored.
Select the “Folder” button, then select the current Snapshot that was just created
Select the “Tool” button. Under the line graph column, select “EGR L COMAND” and “EGR LIFT.”
Select the “Line Graph” button
If the EGR LIFT graph follows the EGR L COMMAND graph, the EGR value is OK. Troubleshoot other causes for the symptom.
If the EGR LIFT graph is different form the EGR L COMMAND graph, the EGR value is bad. Go to REPAIR PROCEDURE.
Replace a new EGR value.
Disconnect the EGR value connector
Remove the EGR value and gasket
Install the new gasket and EGR value. Torque the nus to 22N.m (16 Ib-ft). Reconnect the EGR value connector and install the intake manifold cover
Connect the Honda diagnostic system to the vehicle again, and clear any stored trouble codes
INstalling for Honda HDS HIM diangostic tool Video: