2003 MODEL COVERAGE

MODEL

BODY CODE ⁽¹⁾

ENGINE (RPO CODE) ⁽²⁾

ENGINE ID

FUEL SYSTEM

IGNITION SYSTEM

Astro & Safari

L, M

4.3L (L35)

SFI

DIS

Avalanche

C, K

5.3L (LM7)

SFI

DIS

.....

8.1L (L18)

SFI

DIS

Aztek

3.4L (LA1)

SFI

DIS

Blazer & Jimmy Canadian

S, T

4.3L (LU3)

CSFI

DIS

Bravada

S, T

4.2L (LL8)

SFI

DIS

Cab & Chassis

6.0L (LQQ4)

SFI

DIS

.....

....

6.6L (LB7)

Turbo Diesel

N/A

.....

8.1L (L18)

SFI

DIS

Chevy Express & Savana

4.3L (LU3)

CSFI

Magnetic ⁽³⁾

.....

4.8L (LR4)

SFI

DIS

.....

5.3L (LM7)

SFI

Magnetic ⁽³⁾

.....

6.0L (LQ4)

SFI

DIS

Cutaway

6.0L (LQ4)

SFI

DIS

.....

6.5L (L65)

Turbo Diesel

N/A

Envoy

S, T

4.2L (LL8)

SFI

DIS

Envoy XL

S, T

4.2L (LL8)

SFI

DIS

.....

....

5.3L (LM4)

SFI

DIS

Escalade

5.3L (LM7)

SFI

DIS

.....

6.0L (LQ9)

SFI

DIS

Escalade ESV & EXT

6.0L (LQ9)

SFI

DIS

Montana & Venture

U, X

3.4L (LA1)

SFI

DIS

.....

6.0L (LQ4)

SFI

DIS

Rendezvous

3.4L (LA1)

SFI

DIS

RV Cutaway

6.0L (LQ4)

SFI

DIS

Sierra & Silverado

C, K

4.3L (LU3)

CSFI

Magnetic ⁽³⁾

.....

4.8L (LR4)

SFI

DIS

.....

5.3L (LM7)

SFI

DIS

.....

6.0L (LQ4)

SFI ⁽⁴⁾

DIS

.....

6.0L (LQ4/KL6)

SFI ⁽⁵⁾

DIS

.....

6.0L (LQ4/KL8)

SFI ⁽⁶⁾

DIS

.....

6.6L (LB7)

Turbo Diesel

N/A

.....

8.1L (L18)

SFI

DIS

Silhouette

3.4L (LA1)

SFI

DIS

Sonoma & S10 Pickup

2.2L (L43)

SFI ⁽⁷⁾

DIS

.....

S, T

4.3L (LU3)

CSFI

Magnetic ⁽³⁾

SSR

.....

5.3L (LM4)

SFI

DIS

Suburban

C, K

5.3L (LM7)

SFI

DIS

.....

5.3L (L59)

SFI ⁽⁷⁾

DIS

.....

6.0L (LQ4)

SFI

DIS

.....

8.1L (L18)

SFI

DIS

Tahoe

C, K

4.8L (LR4)

SFI

DIS

.....

5.3L (LM7)

SFI

DIS

.....

5.3L (L59)

SFI ⁽⁷⁾

DIS

Tracker

J & E

2.0L (L34)

MFI

DIS

.....

2.5L (LE8)

SFI

DIS

TrailBlazer

S & T

4.2L (LL8)

SFI

DIS

.....

5.3L (LM4)

SFI

DIS

Vue

.....

2.2L (L61)

SFI

DIS

.....

3.0L (L81)

SFI

DIS

Yukon

.....

4.8L (LR4)

SFI

DIS

.....

5.3L (LM7)

SFI

DIS

.....

5.3L (L59)

SFI ⁽⁷⁾

DIS

.....

6.0L (LQ4)

SFI

DIS

Yukon XL

C, K

5.3L (LM7)

SFI

DIS

.....

5.3L (L59)

SFI ⁽⁷⁾

DIS

.....

6.0L (LQ4)

SFI

DIS

.....

8.1L (L18)

SFI

DIS Magnetic

⁽¹⁾	Series designation.

⁽²⁾	Engine code is stamped on engine block. See ENGINE CODE LOCATION .

⁽³⁾	Uses Enhanced Electronic Ignition (EEI), utilizing a camshaft and crankshaft position sensor.

⁽⁴⁾	Gasoline vehicle.

⁽⁵⁾	Bi-fuel vehicle.

⁽⁶⁾	Compressed Natural Gas (CNG) vehicle.

⁽⁷⁾	Flex-fuel vehicle.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Model Coverage

Use the Manual With the Right Hardware

When to See a Mechanic

Rather have a pro handle this?