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For 1990-2009 cars only

Engine Oil Pressure Warning Light Illuminated, Engine Oil Seepage/Leaking Onto Ground in Extremely Low Ambient Temperatures (Replace PCV Hose and Bracket/Install New Catch Tank Cover)

Subject:Engine Oil Pressure Warning Light Illuminated, Engine Oil Seepage/Leaking Onto Ground in Extremely Low Ambient Temperatures (Replace PCV Hose and Bracket/Install New Catch Tank Cover)

Models:2005-2007 Chevrolet W-Series Medium Duty Tilt Cab
2005-2007 GMC W-Series Medium Duty Tilt Cab
2005-2007 NPR/NQR/NRR Commercial Models
with 5.2L 4HK1-TC Diesel Engine



Condition

Some customers may comment that the Engine Oil Pressure warning light is illuminated or they notice engine oil seepage or leaking onto the ground. This condition is only prevalent in regions with extremely cold ambient temperatures at or below -30°C (-22°F) and when the vehicle is operated for extended periods.

Cause

The positive crankcase ventilation (PCV) vent hose may be plugged with frozen water. Blow-by gas and moisture accumulates, freezes and then can plug the PCV draft tube, causing excessive pressure in the crankcase.

Isuzu expects most of these conditions to occur in Alaska or Northern Canada. Dealers outside of the regions where extremely cold temperatures are encountered should NOT order the part listed below. Dealers outside of cold weather regions that install this part will be subject to warranty claim review.

Correction

A new PCV hose, mounting bracket and catch tank cover are available to correct this condition. Use the following procedure and the part numbers listed below.

  1. Tilt the cab up.

  2. Object Number: 1870790  Size: SH
  3. Disconnect the PCV hose clamp (1) at the catch tank.
  4. Disconnect the PCV hose (2) from the catch tank.

  5. Object Number: 1870793  Size: SH
  6. Disconnect the PCV hose from the hose bracket (2) near the oil filter.
  7. Loosely install the new PCV hose bracket (1) at the transmission bell housing.
  8. Important: Note the routing of the PCV hose. This routing will need to be followed to install the new hose.

  9. Remove the PCV hose.
  10. Remove the PCV hose clamp from the old hose and install on the new hose. Discard the old PCV hose.
  11. Install the new PCV hose onto the vehicle. Follow the hose routing as noted in step 6.
  12. Connect the PCV hose onto the catch tank and attach the hose clamp into the proper position.

  13. Object Number: 1870796  Size: SH
  14. Install the new catch tank cover (1). Install the cover from the upper side of the catch tank and slide down between the catch tank and bracket (2).

  15. Object Number: 1870799  Size: SH

    Important: 

       • The hose cutout area must face and contact the flywheel housing surface.
       • The new hose location may allow crankcase oil vapor to accumulate at the bell housing location. This is considered normal. Do not confuse this as an actual oil leak.

  16. Position the bottom of the new PCV hose (1) into the new bracket (2) at the bell housing and tighten into position.
  17. Tighten
    Tighten the bolt to 19 N·m (14 lb ft).

  18. Close the cab.

Parts Information

For Chevrolet and GMC Models

 

Part Number

Description

Qty

98027841

Hose, PCV Rubber

1

98030387

Bracket, PCV Tube

1

98024528

Cover, F/Tnk Catch

1

94009841

Bolt

1

For Isuzu Models

 

Part Number

Description

Qty

8-98027-841-0

Hose, PCV Rubber

1

8-98030-387-0

Bracket, PCV Tube

1

8-98024-528-0

Cover, F/Tnk Catch

1

0-28090-816-0

Bolt

1

Parts are to be obtained from AIPDN.

Warranty Information

For vehicles repaired under warranty, use:

Labor Operation

Description

Labor Time

J0910

Breather, Crankcase Ventilation - Replace

0.2 hr