Dtc P1404 – Egr Stuck Closed - Isuzu Trooper 1999 Workshop Manual

6E–414
TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Step
1 Was the "On-Board Diagnostic (OBD) System Check"
performed?
2 1. Ignition "ON," engine "OFF", review and record
Tech 2 Failure Records Data.
2. Operate the vehicle within Failure Records
conditions as noted.
3. Using a Tech 2, monitor "DTC inf. for DTC P1404
until the DTC P1404 test runs. Note the result.
Does the Tech 2 indicates DTC P1404 failed this
ignition?
3 1. Disconnect the EGR valve harness connector.
2. Inspect the EGR valve and connectors for damaged
pin or terminals.
Were there any damaged pins or terminals?
4 Repair the damaged pin or terminal.
Is the action complete?
5 1. Remove EGR valve from Engine.
2. Inspect EGR valve for any excessive carbon
deposit on EGR shaft.
3. Inspect for any foreign material inside of EGR valve.
Was excessive carbon deposit on EGR valve shaft
and/or foreign material in EGR valve ?
6 1. Clean up EGR valve shaft and inside of EGR valve.
2. Remove foreign material from EGR valve.
3. Visually inspect damage of pintle and seat to see if it
is bent. If damaged leakage may occur.
Was there any severe damage which affects function?
7 1. Install the EGR valve.
2. Ignition "OFF".
3. Install the Tech 2.
4. Run the engine at idle.
5. On the Tech 2, select EGR Control Test.
6. Use the "UP" arrow to increase the EGR from 0% to
40%.
Did EGR work properly?
8 1. Reset the learned zero EGR valve position.
2. Repeat step 7.
Did EGR work properly?
DTC P1404 – EGR Stuck Closed
Action Value(s) Yes
— Go to Step 2
— Go to Step 3
Go to Step 4
—
— Verify repair
Go to Step 6
—
Go to Step 8
—
— —
— Verify repair
No
Go to OBD
System
Check
Refer to
Diagnostic
Aids
Go to Step 5
—
Go to Step 7
Verify repair
Go to Step 7
Go to Step 8
Go to Step 9