AUTOOL SDT205S · Adjustable Automotive Smoke Leak Detector with Pressure and Flow Monitoring
Control Airflow While Watching Pressure and Flow
Use Air Mode to check pressure and flow, then switch to Smoke Mode to trace the visible leak path. SDT205S combines a built-in pump, separate pressure and airflow indications, and an adjustable flow knob so technicians can match delivery to the connected permitted low-pressure test line without an external compressor.
- Separate Air And Smoke Modes
- Pressure And Flow Feedback
- Adjustable Built-In Airflow
- Oil Drain Valve
- About 5-Second Smoke Start

Key Features
Air and Smoke Modes with Flow Adjustment
Air Mode and Smoke Mode
Switch between Air Mode for pressure and flow checks and Smoke Mode for visual leak location.
Built-In Air Pump
No external air compressor is required. The built-in air pump keeps setup simple for workshop and mobile repair use.
Pressure Gauge Monitoring
The pressure gauge lets you monitor line pressure. A falling reading may indicate a leak that needs further inspection.
Flow Meter Window
The flow meter window lets you monitor airflow through the connected test line.
Flow Adjustment Knob
Use the flow adjustment knob to match airflow to the connected test line and test setup.
Smoke Starts in About 5 Seconds
Smoke starts quickly to reduce waiting time during leak checks. The connected test line may fill with smoke in about 30 seconds, depending on system volume and sealing.
EVAP and Vacuum Leak Checks
Supports EVAP and vacuum-related low-pressure leak tests when adapters and ports that match the vehicle test connection are used.
Vehicle System Leak Checks
Use it for low-pressure leak checks on intake, exhaust, crankcase, fuel-tank, vehicle-sealing, and line-fitting systems.
Oil Drain Valve
The oil drain valve helps remove old testing oil before refilling, supporting cleaner maintenance and more stable smoke output.
Portable Design
The compact body, handle, hanging setup, cone adapter, and airbag adapter make the unit easier to position, store, and connect during testing.
Overheat and Low-Temperature Protection
The protection system shuts down power when the internal temperature exceeds 75°C and supports low-temperature use.
3 Years Warranty Support
Main unit: 3-year warranty. Standard accessories: 1-year warranty. Warranty Policy.
Safety & Compatibility
Use the Correct Pressure, Medium, and Vehicle Procedure
12V Power and Built-In Air Pump
Connect SDT205S to a 12V DC vehicle battery before use. The built-in air pump provides the test airflow, so you do not need an external compressor.
Watch Pressure and Airflow Within Service Limits
SDT205S outputs less than 15 psi and less than 6 L/min. Use the pressure gauge and flow meter to watch the test, and open the airflow regulator gradually. Adjusting flow does not allow you to exceed the system’s permitted test pressure.
Add 10–15 mL of Testing Oil
Use liquid paraffin or baby oil as testing oil. Add 10–15 mL before use and do not overfill.
Limit Continuous Use to 8 Minutes
Do not run SDT205S continuously for more than 8 minutes. Automatic overheat protection stops operation above 75°C. Let the unit cool before restarting.
Do Not Use for Direct High-Pressure A/C Testing
Do not introduce smoke into high-pressure systems or any component excluded by the vehicle or component service procedure. SDT205S cannot directly pressure-test an automotive A/C system; use smoke only as an indirect aid on an isolated section where permitted.
Hot Surface Warning
The round metal housing can become hot during use. Avoid touching hot surfaces directly.
Use Smoke to Locate the Leak
Use visible smoke to locate the leak area, then repair and retest. If no smoke appears, recheck isolation, flow, and the test setup before continuing.
Never Refill While Running
Do not refill testing oil while SDT205S is running.
Drain Excess Oil First
Drain excess oil before operation if the unit has been overfilled.
Regulator Changes Airflow Only
Use the airflow regulator to change flow, not test pressure.
Cool Before Restarting
Let the unit cool before restarting after overheat protection is triggered.
Test Results
Interpret Gauge, Flow, and Smoke by Test Stage
Flow or Pressure Changes
Use pressure and flow behavior under the configured, sealed test setup to guide the next leak inspection step.
Visible Smoke Escape
Check that the outlet is not an intentional opening, then inspect, repair and retest the exact area.
No Visible Smoke
Verify access, isolation, valve state and smoke delivery before moving to functional diagnosis or another test method.
Specifications
SDT205S Specifications
| Smoke Output & Protection | |
|---|---|
| Working Principle | Low Oxygen Combustion |
| Test Oil Filling Volume | 10-15ml |
| Rated Output Pressure | <15 psi machine-rated output; use the target-system procedure. |
| Rated Output Flow | <6L/min |
| High-Temperature Protection | Stops working above 75°C |
| Response Time | Produces smoke in 5 seconds |
| Power & Physical Size | |
| Input Power | DC12V |
| Rated Power | 65W |
| Net Weight (Main Unit) | 3.2kg |
| Main Unit Dimensions | 295mm*295mm*207mm |
| Monitoring & Controls | |
| Flow Meter Window | Yes |
| Pressure Gauge | Yes |
| Air Source Type | Built-in Air Pump |
| Mode Output | Air ModeSmoke Mode |
| Flow Adjustment Knob | Yes |
| Oil Drain Valve | Yes |
| Fault Indicator Light | Yes |
Manual & Downloads
Use the Manual for Setup and Test Pressure

AUTOOL SDT205S User Manual
Open the PDF manual for SDT205S Air and Smoke modes, pressure and flow monitoring, output adjustment, oil draining, safety, and troubleshooting.

Package
What’s Included
- Power cord ×1Included
- Smoke outlet hose ×1Included
- Cone adapter ×1Included
- Valve core wrench ×1Included
- EVAP connector ×1Included
- Filling bottle ×1Included
- Universal airbag adapter ×1Included
- Universal hard rubber plug ×1 setIncluded
- Universal small adapter ×1Included
- User manual ×1Included
FAQs
Flow, Pressure, and Smoke Questions
What Testing Oil Should I Use for SDT205S?
If dedicated smoke-testing oil is unavailable, use liquid paraffin or baby oil. Testing oil is usually not included.
How Much Testing Oil Should I Add?
Add 10–15 mL testing oil before use. Do not add more than 15 mL each time. Refill only when smoke becomes thin, and drain remaining testing oil before adding fresh oil. If too much oil is added accidentally, drain some oil out before operation.
Can SDT205S Directly Test Automotive A/C System Leaks?
No. The automotive A/C system operates at about 1.7–3.0 MPa output pressure, while AUTOOL smoke leak detectors generate much lower pressure. SDT205S cannot directly pressure-test the automotive A/C system for leaks. Use smoke only to help inspect an A/C line section after isolating and pressurizing it according to the service procedure.
How Can I Use Smoke to Check an Isolated A/C Line Section?
First isolate and pressurize the A/C line segment according to the vehicle or A/C service procedure. Then apply smoke near the suspected area and observe whether escaping airflow disturbs the smoke. If escaping air moves the smoke, inspect that area for a possible leak.
Can SDT205S Detect EVAP Leaks?
Yes. This EVAP smoke machine supports permitted low-pressure leak checks. Use the EVAP adapter or service tool that matches the vehicle test port.
What Systems Can SDT205S Test?
SDT205S supports low-pressure checks for intake, exhaust, vehicle-sealing, crankcase, fuel-tank, EVAP, vacuum-line, and line-fitting systems. It is not a direct pressure tester for high-pressure A/C systems.
What Power Supply Does SDT205S Need?
SDT205S runs on a 12V DC vehicle battery. Connect it to a 12V vehicle battery before operation.
Can I Adjust the Pressure on SDT205S?
SDT205S uses fixed output below 15 psi. Its flow adjustment knob controls airflow, not pressure mode. If separate Standard and EVAP pressure modes are required, compare SDT208.
What Accessories Are Included?
Accessories vary by model and package option. Depending on the package, items may include rubber adapters, a cone adapter, an airbag adapter, EVAP testing tools, a smoke hose, and a power cable. Other items may include a testing oil bottle, user manual, warranty card, and quality certificate. Check the SDT205S package contents on the product page for the exact included items.
How Do AUTOOL Smoke Leak Detector Models Differ?
- External-air EVAP: SDT101/103 — 3.2 kPa (0.46 psi).
- Built-in pump: SDT106 <12 psi; SDT203/205/205S <15 psi; SDT206 dual pumps <18 psi.
- Dual pressure: SDT208 — 35 psi Standard / 10 psi EVAP.
Also compare flow monitoring, modes, oil drainage, and accessories.
How Long Is the Warranty for SDT205S?
Main unit: 3-year warranty. Standard accessories: 1-year warranty. Warranty Policy.





