The ATG Direct Injection and Induction Systems Diagnostics manual used the ATG ‘High Level Indicator’ approach to present the information in a way that is relevant to the actual diagnostic process.
The ATG ‘High Level Indicator’ approach is universal and can be applied to any direct Injection and modern intake systems regardless of the manufacturers’ many names and configurations.
This is achieved by introducing systems in layers:
- Core components and operating modes
- Categories of variations
- Tailored high-level indicators by system, symptom, and code
- Universal diagnostic techniques from easiest/most informative to hardest/least informative
- Manufacturer-specific traps and fault patterns
These layers allow for initial high-level testing which can increase your diagnostic accuracy and trim your diagnostic times and can be applied to the following systems:
- Gasoline Direct Injection
- Electronic Throttle Controls
- Variable Intake Manifolds (Runners & Plenums)
- Turbocharging & Controls
- High Flow Crankcase Breathing
Most manufacturers’ flow charts for Gasoline Direct Injection (GDI) performance codes involve time-consuming and invasive steps that usually result in replacing parts.
The ATG ‘High Level Indicator’ approach asks a much more important question: “What is the ‘Desired vs. Actual’ pressure relationship under various conditions?”
The answer to this question will drive all other diagnostic decisions.
This manual discusses many possible causes not included in most manufacturers’ flow charts:
- Camshaft/variable valve timing
- Camshaft lobe health & pump lift
- Rail pressure sensor calibration
- Low pressure supply side & fuel quality
- Idle speed
With the ATG ‘High Level Indicator’ approach, you’ll be able to build the most effective diagnostic path, shaving hours from published diagnostics and increasing accuracy.
Table of Contents overview
SECTION 1 Gasoline Direct Injection
Low & High Pressure
Component Replacement
High Level Tests
Physical Inspection
Scan Tool & Lab Scope Tests
Intake Valve Cleaning
Combo Port/Direct Systems
SECTION 2 Electronic Throttle Controls
Components
Sensor Diagnostics
Throttle Motor Testing
Scan Tool Strategies
Lab Scope examples
SECTION 3 Variable Intake Manifolds
Plenum Shifting
Intake 'Bounce'
Scan Tool & Lab Scope Tests
SECTION 4 Turbochargers
Exhaust Side Boost Control
Intake Side Boost Control
Scan Tool & Lab Scope Tests
SECTION 5 Crankcase Breathing
European high-flow systems
Manual Testing
Crankcase vacuum testing
