EGR Valve - DTCs P0400, P1400, and P1401 EGR

05.1-26

Sedan Range

DATE
6/97 Amended 3/99

MODEL
1995-97 MY Sedan (4.0L) Range

VIN
NA 720001-792000
SC 774096-792000

EGR Valve Sticking/Fails to Close - Revised EGR Valve

ISSUE:





A revised EGR valve (part no. LHE 1550AB) was introduced as a running change from VIN 792000 approximately. The revised valve, Illustration 1, can be identified by the date code 24862A or later (2486 indicates the 248th day of 1996.) The valve has a revised pintle design that helps prevent sticking to solve concerns with rough idling.The following Diagnostic Trouble Codes may be present:

^ DTC P0400 - EGR temperature sensor circuit malfunction

^ DTC P1400 - EGR valve position malfunction

^ DTC P1401 - EGR valve position circuit out of range (high or low voltage)

ACTION:
When diagnosing a customer complaint on a 1995-97 MY Sedan Range (NA) or 1996-97 MY XJR (SC) vehicle within the above VIN range that exhibits the above concerns and/or DTCs, proceed as described:

1. Verify the presence of the EGR DTCs on the previous page and clear them.

2. Remove the EGR valve and gasket.

3. Check the EGR pipes for loose carbon and blow out, if necessary.

NOTE:
Do not attempt to remove carbon by scraping. Scraping can cause the carbon deposit to come loose in the future, causing the replacement valve to stick or remain open.

NOTE:
Do not replace the Mass Air Flow sensor (MAF) or the Engine Control Module (ECM) to attempt to repair the above complaints. Replacing these components will not repair these complaints.

4. If the EGR valve has a date code prior to 24862A and EGR DTCs P0400, P1400, or P1401 are stored, install a revised EGR valve and new gasket. If not, proceed to step 5.

5. If DTCs P0727 and/or P1775 are stored, or the engine is idling rough, and no EGR DTCs are stored, inspect the EGR valve as follows:

^ Turn the EGR valve over and check if the pintle is completely closed. The highest part of the pintle must be flush with the base of the EGR valve.

^ Use a screwdriver to push the pintle all the way down until it bottoms out. Release the pintle and verify that it returns to the closed position.

^ If the pintle moves freely and closes properly, do not replace the EGR valve. If the pintle fails to close or sticks, install a revised EGR valve and new gasket.

PARTS INFORMATION:

DESCRIPTION PART NUMBER QTY
EGR valve LHE 1550AB 1
EGR valve gasket NBC 4774AB 1

WARRANTY INFORMATION:

FAULT R.O. TIME
CODE NUMBER DESCRIPTION ALLOWANCE
BH BD 42 1745.01 Replace EGR valve 0.15 hrs.