- Used to check fuel system restriction on diesel engines with Compuchek test ports.
- Fits Compuchek test ports on the fuel systems of Cummins, International, and Detroit Diesel engines as well as other diesel engines that have been outfitted with the Compuchek test ports.
- Consists of a hose assembly with a female Compuchek fitting on one end and a 3-1/2", 30 inHg vacuum gauge on the other.The ATCL-TU-32-21 Compucheck Diesel Fuel Restriction Tester is a precision diagnostic tool designed to measure fuel system restriction (vacuum) on diesel engines equipped with Compucheck test ports. Unlike pressure testers, this tool evaluates the inlet side of the fuel system, allowing technicians to identify restrictions caused by clogged filters, collapsing lines, or fuel supply issues before they lead to performance loss or component failure.
The tester consists of a female Compucheck quick-connect fitting, a 6-foot flexible hose, and a 3-1/2" analog vacuum gauge calibrated to 30 inHg (inches of mercury). This configuration allows direct connection to the fuel system without disassembly, providing immediate feedback on restriction levels during engine operation.
By measuring vacuum rather than pressure, the ATCL-TU-32-21 gives technicians a clear view of how hard the fuel system is working to draw fuel from the tank. Elevated vacuum readings indicate restriction upstream of the injection pump or lift pump—often before symptoms become severe enough to trigger faults or drivability issues.
The extended hose length enables live monitoring during idle, load, or road testing, making it possible to diagnose intermittent or load-dependent restriction problems that are not visible during static testing.
Compatible with a wide range of diesel platforms—including Cummins, International, and Detroit Diesel engines equipped with Compucheck ports—this tool is a critical component in advanced fuel system diagnostics.
Key Features & Benefits
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Vacuum-Based Restriction Testing: Measures fuel system inlet restriction (0–30 inHg range)
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Direct Compucheck Connection: Quick-connect fitting for fast, leak-free hookup
-
3-1/2" Analog Vacuum Gauge: Clear, accurate readings for diagnostic precision
-
6-Foot Hose Assembly: Enables safe monitoring during live engine operation and road testing
-
Wide Engine Compatibility: Works with Cummins, International, Detroit Diesel, and other Compucheck-equipped systems
-
Real-Time Diagnostics: Identifies restriction issues under load conditions
-
Durable Construction: Built for repeated use in professional diesel environments
Typical Applications
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Fuel system restriction testing (pre-filter and supply side)
-
Diagnosing plugged fuel filters or restricted lines
-
Lift pump inlet restriction analysis
-
Troubleshooting low power or fuel starvation issues
-
Preventative maintenance and system health checks
Why It Matters
Fuel restriction is one of the most overlooked causes of diesel performance issues. Unlike pressure problems, restriction builds gradually and can cause:
-
Power loss under load
-
Hard starting
-
Increased injector wear
-
Premature lift pump failure
Without measuring vacuum, these issues are often misdiagnosed as injector or pump failures.
The ATCL-TU-32-21 allows technicians to see restriction directly, making it possible to isolate problems such as:
-
Plugged fuel filters
-
Collapsing suction lines
-
Tank pickup obstructions
Used alongside a pressure tester (like TU-32-20), it provides a complete picture of fuel system health—pressure on the supply side and restriction on the inlet side—resulting in faster, more accurate diagnostics.
The ATCL-TU-32-21 Compucheck Diesel Fuel Restriction Tester is a precision diagnostic tool designed to measure fuel system restriction (vacuum) on diesel engines equipped with Compucheck test ports. Unlike pressure testers, this tool evaluates the inlet side of the fuel system, allowing technicians to identify restrictions caused by clogged filters, collapsing lines, or fuel supply issues before they lead to performance loss or component failure.
The tester consists of a female Compucheck quick-connect fitting, a 6-foot flexible hose, and a 3-1/2" analog vacuum gauge calibrated to 30 inHg (inches of mercury). This configuration allows direct connection to the fuel system without disassembly, providing immediate feedback on restriction levels during engine operation.
By measuring vacuum rather than pressure, the ATCL-TU-32-21 gives technicians a clear view of how hard the fuel system is working to draw fuel from the tank. Elevated vacuum readings indicate restriction upstream of the injection pump or lift pump—often before symptoms become severe enough to trigger faults or drivability issues.
The extended hose length enables live monitoring during idle, load, or road testing, making it possible to diagnose intermittent or load-dependent restriction problems that are not visible during static testing.
Compatible with a wide range of diesel platforms—including Cummins, International, and Detroit Diesel engines equipped with Compucheck ports—this tool is a critical component in advanced fuel system diagnostics.
Key Features & Benefits
- Vacuum-Based Restriction Testing: Measures fuel system inlet restriction (0–30 inHg range)
- Direct Compucheck Connection: Quick-connect fitting for fast, leak-free hookup
- 3-1/2" Analog Vacuum Gauge: Clear, accurate readings for diagnostic precision
- 6-Foot Hose Assembly: Enables safe monitoring during live engine operation and road testing
- Wide Engine Compatibility: Works with Cummins, International, Detroit Diesel, and other Compucheck-equipped systems
- Real-Time Diagnostics: Identifies restriction issues under load conditions
- Durable Construction: Built for repeated use in professional diesel environments
Typical Applications
- Fuel system restriction testing (pre-filter and supply side)
- Diagnosing plugged fuel filters or restricted lines
- Lift pump inlet restriction analysis
- Troubleshooting low power or fuel starvation issues
- Preventative maintenance and system health checks
Why It Matters
Fuel restriction is one of the most overlooked causes of diesel performance issues. Unlike pressure problems, restriction builds gradually and can cause:
- Power loss under load
- Hard starting
- Increased injector wear
- Premature lift pump failure
Without measuring vacuum, these issues are often misdiagnosed as injector or pump failures.
The ATCL-TU-32-21 allows technicians to see restriction directly, making it possible to isolate problems such as:
- Plugged fuel filters
- Collapsing suction lines
- Tank pickup obstructions
Used alongside a pressure tester (like TU-32-20), it provides a complete picture of fuel system health—pressure on the supply side and restriction on the inlet side—resulting in faster, more accurate diagnostics.