D002/96 ROUGH IDLE AND/OR ENGINE STALL AFTER COLD START

AFFECTED MODELS

1994-96 323/Protege with the following engines: B6 and BP

1994-96 MX-3 with B6 engine.

1990-96 MX-5 with B6 and BP engines.

1994-96 626/MX-6 with a 4 cyl. engine and a VIN 1YVGE**C*T5580486 and lower.

DESCRIPTION

Rough idle and/or engine stall may occur after cold start and continue until the engine reaches normal operating temperature. This condition may occur in cold ambient temperatures 14 degrees to 50 degrees (F) (-10 degrees to 10 degrees C).

The following causes may result in poor driveability in cold ambient temperatures:

  1. Vehicles with long oil pump control plungers as a countermeasure for HLA noise. The concern may be caused when the oil pump control plunger becomes struck. When this occurs, the oil pressure becomes excessive. The high pressure is applied directly to the HLA, which pushes the valve down and prevents complete closing.

  2. B6 DOHC Engines Only . Compression loss due to poor seating of the exhaust valve caused by thermal expansion.

DIAGNOSTIC PROCEDURE

Follow this procedure if the vehicle has a B6 DOHC engine. If the vehicle is not equipped with a B6 DOHC engine, perform

  • Allow the vehicle to sit for at least eight hours (overnight) in cold ambient temperatures [50 degrees F (10 degrees C)].
    1. Prepare to measure the engine oil pressure.

    2. Start the engine.

    3. Measure the oil pressure immediately after starting (during fast idle).

      NOTE: If the diagnostic inspection is inconclusive, proceed to step 4.

    4. Allow the engine to run for 2 or 3 minutes.

    5. Raise engine RPM to 3,000.

    6. Measure the oil pressure.

      • If the oil pressure is not significantly different from the first measurement the problem may be caused by exhaust valve expansion.

      • If the pressure is over 980 kPa (10 kgf/cm, 140 psi) the cause may be a stuck oil plunger.

    REPAIR 1

    Replace the oil pump with a new one.

    NOTE:

    • Oil pump replacement is necessary. If the plunger was seized, there is a possibility that the control plunger cylinder is worn.

    • If replacing the pump with a pre-modified oil pump, install the modified plunger to prevent concern reoccurence.

    ebt-raster

    PARTS INFORMATION for REPAIR 1

     

    Part Number

    		 

    Description

    		 

    Qty.

    		 

    Inter.

    		 

    Models

     

    New

    		 

    Old

     

    B6S8-14-100H

    		 

    B6S8-14-100G

    		 

    Oil Pump

    		 

    1

    		 


    (The new part can be used in place of the old part but the old part can not be used in place of the new part.)

    		 

    323, Protege, MX-3, MX-5 with BP and B6 Engines

     

    FS01-14-115

    		 

    JF01-14-115

    		 

    Control Plunger

    		 

    1

    		 


    (The new part can be used in place of the old part but the old part can not be used in place of the new part.)

     

    FS01-14-100L

    		 

    FS01-14-100K

    		 

    Oil Pump

    		 

    1

    		 


    (The new part can be used in place of the old part but the old part can not be used in place of the new part.)

    		 

    626/MX-6 with 4 Cylinder Engines

     

    FS01-14-115

    		 

    JF01-14-115

    		 

    Control Plunger

    		 

    1

    		 


    (The new part can be used in place of the old part but the old part can not be used in place of the new part.)

    WARRANTY INFORMATION for REPAIR 1

    (Applies To Verified Customer Complaints On Vehicles Covered Under Normal Warranty. Refer To The SRT Microfiche For Warranty Term Information.)

    Warranty Type 
    A
    Symptom Code 
    03
    Damage Code 
    92
    Part Number Main Cause 
    B6S8-14-100
    Quantity 
    1
    Operation Number 
    D010*R* (The asterisk "*" can be any letter, refer to the SRT)
    Labor Hours 
    Refer to the SRT

    REPAIR 2

    Replace exhaust valve and springs with modified parts.

    NOTE: DO NOT replace HLA's to correct this concern.

    PARTS INFORMATION for REPAIR 2

     

    Part Number

    		 

    Description

    		 

    Qty.

    		 

    Inter.

     

    New

    		 

    Old

     

    B660-12-121A

    		 

    B660-12-121

    		 

    Exhaust Valve

    		 

    8

    		 


    (The new part can be used in place of the old part but the old part can not be used in place of the new part.)

     

    B660-12-125A

    		 

    B61P-12-125

    		 

    Valve Spring

    		 

    8

    		 


    (The new part can be used in place of the old part but the old part can not be used in place of the new part.)

    NOTE: Part No. B695-12-121B (exhaust valve) may also be used for this repair.

    WARRANTY INFORMATION for REPAIR 2

    (Applies To Verified Customer Complaints On Vehicles Covered Under Normal Warranty. Refer To The SRT Microfiche For Warranty Term Information.)

    Warranty Type 
    A
    Symptom Code 
    03
    Damage Code 
    97
    Part Number Main Cause 
    B660-12-121A or B660-12-125A
    Quantity 
    8
    Operation Number/Labor Hrs. 
    XX860XR4/7.1 Hrs (MX-3) 
XX860X86/6.6 Hrs. (MX-5)