Symptoms - Fuel System. Chevrolet Express

For 1990-2009 cars only

Makes 🢒 Chevrolet 🢒 2007 🢒 Express - AWD 🢒 General Information 🢒 Vibration Diagnosis and Correction 🢒 Symptoms - Fuel System

Symptoms

Fuel System

Find the symptom in the left column and perform the test/inspection procedure in the right column

Hard Start

Surges /Chuggles

Lack of Power, Sluggishness, or Sponginess

Detonation/Spark Knock

Hesitation, Sag, Stumble

Cuts Out, Misses

Poor Fuel Economy

Rough, Unstable, or Incorrect Idle and Stalling

Backfire

•	Test for proper operation of the Fuel System. Refer to Fuel Pump Electrical Circuit Diagnosis and Fuel System Diagnosis .

•	Inspect for a contaminated fuel condition. Refer to Alcohol/Contaminants-in-Fuel Diagnosis .

•	Test for restricted fuel system.

•	Inspect for lean or rich conditions. Refer to P0171, P0172, P0173 or P0174 conditions for running the DTC.

Hard Start

Surges /Chuggles

Lack of Power, Sluggishness, or Sponginess

Detonation/Spark Knock

Hesitation, Sag, Stumble

Cuts Out, Misses

Poor Fuel Economy

Rough, Unstable, or Incorrect Idle and Stalling

Dieseling, Run-On

Test for proper operation of the fuel injectors. Refer to the following diagnostics:

•	Fuel Injector Balance Test with Special Tool or Fuel Injector Balance Test with Tech 2

•	Fuel Injector Solenoid Coil Test

Surges /Chuggles

Lack of Power, Sluggishness, or Sponginess

Hesitation, Sag, Stumble

Cuts Out, Misses

Rough, Unstable, or Incorrect Idle and Stalling

Inspect the Evaporative Emission (EVAP) System for excess fuel in the EVAP lines and/or in the EVAP canister. Refer to Evaporative Emissions Hose Routing Diagram .