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For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1996 🢒 Blazer - 2WD 🢒 Engine 🢒 Engine Mechanical - 2.2L 🢒 Drive Belt Diagnosis

Drive Belt Diagnosis Vibration

Drive Belt Vibration Problems

Step

Action

Value

Yes

No

Definition:

1

Check for loose or missing fasteners.

Are there loose or missing fasteners?

 

Go to Step 2

Go to Step 3

2

Re-torque or replace as necessary.

Refer to Fastener Tightening Specifications.

Is the repair complete?

 

System OK

 

3

Check for damaged fan blades.

Are there damaged fan blades?

 

Go to Step 4

Go to Step 5

4

Replace as necessary.

Refer to Fan Clutch.

Is the replacement complete?

 

System OK

 

5

Check for a bent fan clutch or coolant pump shaft.

Is the fan clutch or coolant pump shaft bent?

 

Go to Step 6

Go to Step 7

6

Replace as necessary.

Refer to Coolant Pump.

Is the repair complete?

 

System OK

 

7

Check for bent or cracked brackets.

Are there bent or cracked brackets?

 

Go to Step 8

System OK

8

Replace the brackets as necessary.

Is the repair complete?

 

System OK

 

Drive Belt Diagnosis Falls Off

Drive Belt Falls Off

Step

Action

Value

Yes

No

Definition:

1

Check for loose or missing fasteners.

Are there any loose or missing fasteners?

 

Go to Step 2

Go to Step 3

2

Replace as necessary and then tighten to specifications.

Refer to Fastener Tightening Specifications.

Is the repair complete?

 

Go to Step 3

 

3

Check for a misaligned or a bent pulley, refer to Accessory Drive Belts Inspection.

Are the pulleys aligned properly?

 

Go to Step 4

Go to Step 5

4

Check for a damaged drive belt, refer to Accessory Drive Belts Inspection.

Is the drive belt damaged?

 

Go to Step 5

Go to Step 6

5

Repair or install new parts as necessary.

Is the repair complete?

 

System OK

 

6

Check for a malfunctioning drive belt tensioner, refer to Accessory Drive Tensioner Inspection.

Is the drive belt tensioner malfunctioning?

 

Go to Step 5

Go to Step 7

7

Check for a bent or a cracked bracket.

Are any of the brackets bent or cracked?

 

Go to Step 5

System OK

Drive Belt Diagnosis Whine

Drive Belt Whine

Step

Action

Value

Yes

No

1

Check for a worn accessory component bearing.

Is a bearing making the noise?

--

Go to Step 2

System OK

2

Install new parts as necessary

Is the repair complete?

--

System OK

--

Drive Belt Diagnosis Chirping

Before you diagnose the VCM (L35) 4WAL brake system, obtain a detailed description of when the symptoms occurred from the owner. This information can be useful in duplicating the condition. Begin the diagnosis by inspecting the following components:

    • Connectors
    • Wiring
    • Wire routing and retention
    • All 4WAL system components

A visual inspection may reveal any of the following conditions:

    • A disconnected or loose connector
    • A blown fuse
    • A corroded terminal
    • A misrouted wire

If a visual inspection does not reveal the cause of a malfunction, perform the VCM (L35) Diagnostic System Check. Always start with the VCM (L35) Diagnostic System Check.

Drive Belt Diagnosis Diagnosis

Definitions

The following are symptomatic noises of the accessory drive belt system:

  1. Chirping:
    2. • A high pitched noise that is usually heard once per revolution of a pulley or a belt.
    • It is most common on cold, damp mornings.
    • Verify this condition by squirting water onto the belt. The noise will momentarily stop.
  2. Squeal:
    3. • A loud screeching noise that is caused by a slipping belt (this is unusual for a multiple ribbed belt).
    • The noise occurs when a heavy load is applied to the belt, such as an air conditioning compressor engagement, snapping the throttle, or slipping on a seized pulley.
  3. Whine: A high pitched continuous noise that may be caused by a failed component bearing.
  4. Faint Cycle Rumbling: A low frequency noise heard once per revolution of the belt.
  5. Pilling:
    6. • The random accumulation of rubber dust in the bottom of the multi-ribbed belt grooves.
    • A small amount of pilling is normal.
    • Operation of the drive belt system will not be effected unless the buildup exceeds one third (1/3) of the belt groove depth.

Multiple ribbed, accessory drive belts wear evenly with their pulleys. Unusual wear indicates a correction is needed. The following diagnostic tables will aid in diagnosing drive belt system problems.

Drive Belt Diagnosis Rumble

Drive Belt Rumbling

Step

Action

Value

Yes

No

1

Check for severe pilling.

Is there severe pilling of more than 1/3 of the rib depth?

--

Go to Step 2

System OK

2

Install a new accessory drive belt.

Is the repair complete?

--

System OK

--

Drive Belt Diagnosis Squeal

Drive Belt Squeal

Step

Action

Value

Yes

No

Definition:

1

Check for a misaligned pulley, refer to Accessory Drive Belts Inspection.

Is there a pulley misaligned?

 

Go to Step 3

Go to Step 2

2

Check for incorrect belt length, refer to Accessory Drive Tensioner Inspection.

Is the belt length correct?

 

Go to Step 4

Go to Step 3

3

Repair or install new parts as necessary.

Is the repair complete?

 

System OK

 

4

Check for a malfunctioning drive belt tensioner, refer to Accessory Drive Tensioner Inspection.

Is the tensioner malfunctioning?

 

Go to Step 3

Go to Step 5

5

Check for correct pulley size.

Are the pulleys the correct size?

 

Go to Step 6

Go to Step 3

6

Check for siezed bearings.

Is there a siezed bearing?

 

Go to Step 3

System OK