GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Important: Most fluid leaks can be repaired by visually locating the leak, repairing or replacing the component, tightening fasteners to the correct torque specification or by resealing the gasket surface.

1

  1. Operate the vehicle until it reaches normal operating temperature.
  2. Park the vehicle on a level surface, over a large sheet of paper or other clean surface.
  3. Wait for at least 15 minutes.
  4. Check for oil drips.

Are oil drips present?

Go to Step 2

Go to Step 3

2

Identify the type of fluid and the approximate location of the leak.

Can you identify the type of fluid and the approximate location of the leak?

Go to Step 8

Go to Step 3

3

  1. Visually inspect the suspected area. Use a small mirror to assist in looking at hard to see areas.
  2. Check for leaks at the following locations:
  3. • Sealing surfaces
    • Fittings
    • Cracked or damaged components

Can you identify the source of the leak?

Go to Step 8

Go to Step 4

4

  1. Thoroughly clean the entire engine and surrounding components.
  2. Operate the vehicle for several kilometers at normal operating temperature and at varying speeds.
  3. Park the vehicle on a level surface, over a large sheet of paper or another clean surface.
  4. Wait for at least 15 minutes.
  5. Identify the type of fluid, and the approximate location of the leak.
  6. Using a small mirror to assist in looking at hard to see areas, visually inspect the suspected area.

Can you identify the type of fluid, the source of the leak and the approximate location?

Go to Step 8

Go to Step 5

5

  1. Completely clean the entire engine and surrounding components.
  2. Apply an aerosol-type powder (baby powder, foot powder, etc.) to the suspected area.
  3. Operate the vehicle for several kilometers at normal operating temperature and at varying speeds.
  4. Check for cracked or damaged components.
  5. Identify the type of fluid, and the approximate location of the leak, from the powder surface discoloration.
  6. Using a small mirror to assist in looking at hard to see areas, visually inspect the suspected area.

Can you identify the type of fluid, the source of the leak and the approximate location?

Go to Step 8

Go to Step 6

6

  1. Use J 43330 Dye and Black Light Kit to assist in identifying the type of fluid and the approximate location of the leak. Refer to the manufacture's instructions when using the tool.
  2. Using a small mirror to assist in looking at hard to see areas, visually inspect the suspected area.

Can you identify the type of fluid, the source of the leak and the approximate location?

Go to Step 8

Go to Step 7

7

Check for the following conditions:

    • Higher than recommended fluid levels
    • Higher than recommended fluid pressures
    • Blocked or malfunctioning fluid filters or pressure bypass valve
    • Blocked or malfunctioning engine ventilation system
    • Incorrectly tightened, missing or damaged fasteners
    • Improper sealant or gasket installation
    • Damaged or worn gaskets or seals
    • Damaged or worn sealing surfaces

Can you identify the type of fluid, the source of the leak and the approximate location?

Repair or replace all damaged components

Go to Step 8

8

Check the engine for mechanical damage.

Is there any mechanical damage to the engine?

Repair or replace all damaged components

System OK