For 1990-2009 cars

Table 1: | Momentary Noise On Engine Startup
Table 2: | Intermittent Noise on Idle Only
Table 3: | Noise at Slow Idle
Table 4: | Lifter Noise at High Vehicle Speeds
Table 5: | Noise at Idle, Becomes Louder at High Engine Speed
Table 6: | Valve Noise Regardless of Engine Speed

#### Momentary Noise On Engine Startup

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
DEFINITION: Valve train noise disappears after 1 to 2 minutes
1 | This condition is normal. Oil drains from the lifters which hold the valves open when the engine is not running. The valve lifter needs a few seconds to fill with oil after you start the engine. Did you allow the valve lifters to fill? | -- | No correction is needed | --

#### Intermittent Noise on Idle Only

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
DEFINITION: Intermittent noisy on idle only, disappears when engine speed increases
1 |

1. Disassemble the hydraulic lifters.
2. Check the lifters for any dirt. Check the lifters for a pitted or damaged check ball.

Are the lifters dirty? Are the lifters damaged?

--

Go to Step 2

System OK

2 | Replace the valve lifter. Refer to Valve Lifter Replacement | -- | -- | --

#### Noise at Slow Idle

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
DEFINITION: Noisy at slow idle or with hot oil; quiet at higher engine speeds or with cold oil
1 | Inspect the valve lifter for high lay down rate. Does the valve lifter have a high leakdown rate? | -- | Replace the faulty valve lifter | No correction is needed

#### Lifter Noise at High Vehicle Speeds

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
DEFINITION: Valve lifters noisy at high vehicle speeds, quiet at low speeds
1 | Check for a high engine oil level. An oil level above the FULL mark allows the crankshaft counterweights to churn the engine oil into foam. When foam is pumped into the valve lifters, the valve lifters become noisy since a solid column of oil ensures proper operation.

Is the engine oil level too high?

--

Drain the engine oil to the proper level

Go to Step 2

2 | Check for a low engine oil level. Oil level below the ADD mark allows the oil pump to pump air at high speeds. This causes noisy valve lifters. Is the engine oil level too low? | -- | Add engine oil as required | Go to Step 3
3 | Check the oil pan. Is the oil pan bent against the oil pump pickup? | -- | Repair as required | Go to Step 4
4 | Check the oil pump screen. Is the oil pump screen bent or loose? | -- | Repair as required | System OK

#### Noise at Idle, Becomes Louder at High Engine Speed

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
DEFINITION: Noisy at idle, becoming louder as engine speed increases to 1500 RPM
1 | This noise is not connected with lifter malfunction. The noise becomes noticeable in the vehicle at 10 to 15 mph L (Low) range, or 30 to 35 mph D (Drive) range. The noise is described as a "ticking" sound. At slow idle, the sound may be entirely gone or appear as a light ticking noise in one more valves. This noise is caused by one or more of the following:

• | Badly worn or scuffed valve tip and rocker arm pad.

• | Excessive valve stem-to-guide clearance.

• | Excessive valve seat runout.

• | Off-square valve spring.

• | Excessive valve face runout.

Are any components damaged or worn excessively?

--

Repair as necessary

Go to Step 2

2 | The noise may be an off-square valve spring. You can eliminate this noise by rotating the valve spring and valve.

1. Crank the engine until the noisy valve is off its seat.
2. Rotate the spring. This will also rotate the valve.
3. Repeat until the valve becomes quiet.
4. If correction is obtained, check for an off-square valve spring.

The valve spring should not be more than a 1.6 mm (1/16 in) off-square.

Is the valve spring off-square?

--

Replace valve spring

System OK

#### Valve Noise Regardless of Engine Speed

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
DEFINITION: Valve lifter noise louder as engine speed increase hot or cold engine.
1 |

1. Check for excessive valve lash.

1.1. | To check for valve lash, turn the engine so that the piston in the cylinder is on TDC of the firing stroke.

1.2. | If valve lash is present, you can move the valve push rod freely up and down a certain amount with the valve rocker arm held against the valve.

2. Check for a worn valve pushrod upper end ball.

Is the valve pushrod upper end ball worn?

--

Replace the valve pushrod and valve rocker arm

Go to Step 2

2 | Check for a bent valve pushrod. Is the valve pushrod bent? | -- | Replace the valve pushrod | Go to Step 3
3 | Check the lubrication system feed to the valve pushrod and check to see if the valve pushrod is properly lubricated. Is the valve pushrod and feed system properly lubricated? | -- | Go to Step 4 | Replace the valve pushrod and valve rocker arm
4 | Check for a loose or damaged valve rocker arm. Is the valve rocker arm loose or damaged? | -- | Replace the valve rocker arm | Go to Step 5
5 | If you do not need to replace the valve pushrod or the valve rocker arm, this indicates trouble in the valve lifter or camshaft. Is the camshaft worn or damaged? | -- | Replace the camshaft and valve lifters | Replace the valve lifter(s) as necessary