Section 429 (Engine Controls Self-Diagnostics - 6.0L Bi-Fuel & CNG): Introduction

WARNING: This page is about a different car, the 2003 GMC Savana and 2003 Chevrolet Chevy Express. However, it is still accessible from the selected car via links, so may be relevant.

Chevy Express & Savana vehicles are available as a Bi-Fuel vehicle (RPO KL6) or as a CNG only vehicle (RPO KL8). This alternative fuels article applies to both versions. This article should be used in conjunction with the SELF-DIAGNOSTICS - 4.8L, 5.3L, 6.0L EXPRESS & SAVANA - GASOLINE article. This article covers only the Bi-Fuel & CNG self-diagnostics. To properly diagnose and repair this vehicle, follow DIAGNOSTIC STARTING POINT - ENGINE CONTROLS under SELF-DIAGNOSTIC SYSTEM. If no Diagnostic Trouble Codes (DTC) are present and a no-start condition exists, see NO-START DIAGNOSIS in BASIC DIAGNOSTIC PROCEDURES - 6.0L CHEVY EXPRESS, SAVANA, SIERRA & SILVERADO - BI-FUEL & CNG article. If no DTCs are present and a driveability condition exists, see TROUBLE SHOOTING - NO CODES - 6.0L CHEVY EXPRESS, SAVANA, SIERRA & SILVERADO - BI-FUEL & CNG article for diagnosis by symptom (i.e., ROUGH IDLE, ENGINE STALLS, etc.).