AUTOOL CT400 GDI/EFI/FSI 6-Cylinder Fuel Injector Cleaning Machine & Tester
US$575.00 Original price was: US$575.00.US$509.00Current price is: US$509.00.
- Standard and GDI Injector Coverage
- Match the Injector Drive
- Compare Six Injectors at Once
- Complete Clean-and-Retest Workflow
- Standard and GDI Injector Coverage: Clean and test compatible standard, GDI, EFI, and long-body FSI gasoline injectors on one six-position bench.
- Match the Injector Drive: Select 12 V, 70 V, or 120 V to support different standard and direct-injection injector requirements.
- Compare Six Injectors at Once: View leakage, spray pattern, and relative delivery side by side to identify imbalance before replacement or reinstallation.
- Complete Clean-and-Retest Workflow: Combine ultrasonic cleaning, operating-condition tests, reverse flushing, and matched retesting to verify whether service changed the result.
- 3-Year Warranty Main unit 3 years · Accessories 1 year
- 90-Day Returns Eligible returns within 90 days
- Official Store Genuine products · Direct support
AUTOOL CT400 · 6-cylinder multi-voltage GDI injector service bench
GDI / EFI / FSI Fuel Injector Cleaning and Testing
The AUTOOL CT400 is a six-injector, multi-voltage fuel injector cleaner and tester for compatible standard, GDI, EFI, and FSI injectors. CT400 provides 12V, 70V, and 120V injector-drive settings, ultrasonic cleaning, spray-pattern and leak tests, reverse flushing, optional cleaning without injector removal, fluid recovery, and organized accessory storage.
- GDI / EFI / FSI
- 12V / 70V / 120V
- 6-Cylinder Design
- Ultrasonic Cleaning

Core service capabilities
Key Features
CT400 combines wide injector compatibility, three voltage modes, 6-cylinder testing, 3 cleaning and 9 testing functions, ultrasonic cleaning, digital control, fluid recovery, and accessory storage.
GDI / EFI / FSI Injector Support
CT400 supports cleaning and testing compatible standard, EFI, FSI, and GDI injectors, including direct-injection applications.
12V / 70V / 120V Selection
Three injector-drive voltage settings cover different standard and GDI injector applications.
6-Cylinder Cleaning And Testing
Six injectors can be cleaned or tested together to improve workshop efficiency and compare spray or volume performance side by side.
3 Cleaning And 9 Testing Functions
CT400 provides 12 cleaning and test modes, including ultrasonic cleaning, simulated operating conditions, spray-pattern and leak tests, reverse flushing, and optional cleaning without injector removal.
Ultrasonic Cleaning
Pulse signals and ultrasonic vibration with cleaning fluid help remove carbon and impurities inside injectors.
Speed And spray-pattern Tests
Idle, medium-speed, high-speed, acceleration, and variable-speed modes simulate several engine conditions. Three spray-pattern modes help compare injector output.
Leakage And Reverse Flushing
Leakage testing checks injector sealing, and reverse flushing can remove dirt from applicable top-feed injectors or strainers.
Smart Control Panel
The digital panel integrates function selection, working parameters, voltage selection, pressure regulation, and Start / Stop controls.
Drawer Storage And Fluid Recovery
The storage drawer helps organize adapters, while the drain valve helps empty or recover test fluid for routine workshop use.
3 Years Warranty Support
Main unit: 3-year warranty. Standard accessories: 1-year warranty. Warranty Policy.
Step-by-step injector service workflow
Step-by-Step Workflow
Use CT400 to clean and test standard and GDI-family injectors by selecting the correct adapter, fluid, voltage, pressure, and function for the injector type.
Step 01
Identify Injector Type And Voltage
Confirm whether the injector is standard, EFI, FSI, or GDI and select the corresponding adapter and voltage. If unsure, follow the page guidance to increase gradually from 12V to 70V to 120V until the injector operates correctly.
Step 02
Add Cleaning Fluid And Run Ultrasonic Injector Cleaning
Add professional ultrasonic or engine carbon cleaning fluid before starting the ultrasonic function, then use the pulse signal line and ultrasonic vibration to remove deposits.
Step 03
Mount Injectors And Plug Unused Positions
Install up to six injectors securely. When testing one injector, plug the other five unused test positions.
Step 04
Add Test Fluid And Set Pressure
Fill the testing circuit with professional non-corrosive injector test fluid or the stated alcohol alternative, then set pressure and voltage for the injector.
Step 05
Run Cleaning And Testing Functions
Use the control panel to run the selected simulated-speed, spray-pattern, and leak tests.
Step 06
Reverse Flush, Compare, And Recover Fluid
Use reverse flushing only for compatible injectors. Cleaning without injector removal requires the specified optional adapters. Compare results under the same settings, then drain or recover the test fluid.
Result interpretation
How To Read Test Results
Compare standard, EFI, FSI, and GDI injectors only after the correct adapter, drive voltage, test pressure, fluid, pulse, time, and test mode have been selected. Work through the table in order so each observed result leads to a defined adjustment, retest, cleaning, diagnosis, or replacement action.
| What You Observe | What It May Mean | Recommended Next Step |
|---|---|---|
| Drips while closed | Contamination, valve-seat wear, or a sealing fault | Clean and re-test; refer or replace if leakage remains |
| One measuring cylinder fills much less | Restriction, installation leak, channel issue, or injector fault | Check pressure and sealing, swap channels, then clean and repeat |
| Deflected, split, coarse, or dripping spray | Deposit, nozzle damage, or internal mechanical issue | Clean and re-test; use specialist service if unchanged |
| Difference becomes smaller after cleaning | A recoverable restriction may have been reduced | Record the result, renew applicable seals, and verify on the vehicle |
| No measurable improvement | The injector may already be clean or have electrical / mechanical damage | Stop repeated cleaning and continue diagnosis, specialist testing, or replacement |
| Bench results look balanced but the vehicle still misfires | The root cause may be outside the injector system | Check ignition, compression, intake leakage, fuel pressure, and control signals |
Important: Use identical settings when comparing injectors or before-and-after results. If the injector voltage is uncertain, begin at 12V and increase gradually to 70V and then 120V only as required. Do not leave an injector connected to an incorrect high voltage for an extended time. Confirm final limits with the injector specification, service procedure, or CT400 manual.
Fluid, compatibility, and operating limits
Safety & Compatibility
Use the correct test fluid, cleaning fluid, injector voltage, and adapter for CT400. Keep cleaning solution out of the test circuit. Use the manual to verify GDI drive voltage and the required plugs for single-injector testing.
Use Test Fluid For Testing
Use colorless, odorless, non-corrosive professional fuel injector test fluid to check performance and simulate injector working conditions.
75%+ Alcohol As Backup
If professional test fluid is unavailable, medical alcohol with over 75% alcohol content can be used as an alternative for injector testing.
Use Cleaning Fluid For Ultrasonic Cleaning
Use professional fuel injector cleaning fluid formulated for ultrasonic tanks or engine carbon cleaning fluid to remove carbon deposits. Cleaning fluid is typically corrosive and flammable.
Do Not Test With Cleaning Fluid
Do not use corrosive cleaning fluid as injector test fluid because it may damage internal parts, corrode rubber, and cause leakage.
Do Not Run The Ultrasonic Tank Dry
Add carbon cleaning fluid before starting ultrasonic cleaning. Do not run the ultrasonic tank dry; doing so may damage the ultrasonic system.
Select 12V / 70V / 120V For The Injector
Select voltage according to the injector type. If unsure, increase gradually from 12V to 70V to 120V until the injector works correctly, and do not apply incorrect high voltage for a long time.
Compare models
Compare AUTOOL Injector Tester Models
Compare CT400 with CT150, CT160, CT200, CT450, CT500, FN606, and FN608 before choosing the right cylinder capacity, injector compatibility, heating function, voltage range, pump configuration, and test functions.
Compare models
Choose one or more models. CT400 is selected by default.
AUTOOL CT400 is selected. Choose another model for a side-by-side comparison.
AUTOOL CT400 specifications
| Specification | Model 1AUTOOL CT150 | Model 2AUTOOL CT160 | Model 3AUTOOL CT200 | Model 4AUTOOL CT400 | Model 5AUTOOL CT450 | Model 6AUTOOL CT500 | Model 7AUTOOL FN606 | Model 8AUTOOL FN608 |
|---|---|---|---|---|---|---|---|---|
| Core capacity and control | Slide / drag1 / 1 | |||||||
| Power input | 110/220V | 110/220V | 110/220V | 110/220V | 110/220V | 110/220V | 110/220V | 110/220V |
| Cleaning and test modes | 3 Cleaning Functions 9 Testing Functions | 3 Cleaning Functions 9 Testing Functions | 3 Cleaning Functions 9 Testing Functions | 3 Cleaning Functions 9 Testing Functions | 3 Cleaning Functions 10 Testing Functions | 3 Cleaning Functions 12 Testing Functions | 3 Cleaning Functions 12 Testing Functions | 3 Cleaning Functions 12 Testing Functions |
| Measuring-tube capacity | 110ml | 100ml | 110ml | 110ml | 110ml | 110ml | 110ml | 110ml |
| Ultrasonic tank capacity | 1000ml | 2000ml | 1700ml | 2000ml | 2000ml | 1000ml | 550ml | 550ml |
| Pulse-width range | 0-20ms | 0-20ms | 0-20ms | 0-20ms | 0-20ms | 0-40ms Step Size 0.1ms | 0-40ms Step Size 0.1ms | 0-40ms Step Size 0.1ms |
| Time setting range | 0-10min | 0-10min | 0-10min | 0-10min | 0-10min | 0-10min | 0-10min | 0-10min |
| Simulated speed range | 0-7500rpm | 0-7500rpm | 0-7500rpm | 0-7500rpm | 0-7500rpm | 0-7500rpm | 0-7500rpm | 0-7500rpm |
| Ultrasonic cleaning power | 70w | 70w | 70w | 70w | 70w | 70w | 70w | 70w |
| Built-in pump | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 2 |
| Adapter types | 3 Types | 5 Types | 3 Types | 9 Types | 9 Types | 9 Types | 9 Types | 9 Types |
| Injectors tested at once | 4 Fuel Injectors | 4 Fuel Injectors | 6 Fuel Injectors | 6 Fuel Injectors | 6 Fuel Injectors | 6 Fuel Injectors | 6 Fuel Injectors | 8 Fuel Injectors |
| Injector coverage and settings | Slide / drag1 / 1 | |||||||
| Supported injector types | Standard Fuel Injector | Standard Fuel Injector | Standard Fuel Injector | Standard Fuel Injector GDI, EFI, FSI Long Fuel Injectors | Standard Fuel Injector GDI, EFI, FSI Long Fuel Injectors | Standard Fuel Injector GDI, EFI, FSI Long Fuel Injectors | Standard Fuel Injector GDI, EFI, FSI Long Fuel Injectors | Standard Fuel Injector GDI, EFI, FSI Long Fuel Injectors |
| Injector drive-voltage settings | ×Not included | ×Not included | ×Not included | 12V 70V 120V | 12V 70V 120V | 12V 70V 120V | 12V 12V-70V 120V-180V | 12V 12V-70V 120V-180V |
| Menu language options | ×Not included | ×Not included | ×Not included | ×Not included | ×Not included | 2 Types (Chinese, English) | 2 Types (Chinese, English) | 2 Types (Chinese, English) |
| Workshop features | Slide / drag1 / 1 | |||||||
| Heated ultrasonic cleaning | ×Not included | ✓Included · 45℃ | ×Not included | ×Not included | ✓Included · 50℃ | ×Not included | ✓Included · 50℃ | ✓Included · 50℃ |
| Pressure gauge | ✓Included | ✓Included | ✓Included | ✓Included | ✓Included | ✓Included | ✓Included | ✓Included |
| Display | ✓Included | ✓Included | ✓Included | ✓Included | ✓Included | ✓Included | ✓Included | ✓Included |
| Test-fluid level indicator | ✓Included | ✓Included | ✓Included | ✓Included | ✓Included | ✓Included | ✓Included | ✓Included |
| Splash guard | ×Not included | ×Not included | ×Not included | ×Not included | ×Not included | ✓Included | ✓Included | ✓Included |
| Operating-condition simulations | ✓Included | ✓Included | ✓Included | ✓Included | ✓Included | ✓Included | ✓Included | ✓Included |
| Fluid drain/recovery valve | ✓Included | ✓Included | ✓Included | ✓Included | ✓Included | ✓Included | ✓Included | ✓Included |
| Storage drawer | ×Not included | ×Not included | ×Not included | ✓Included | ✓Included | ✓Included | ✓Included | ✓Included |
| Low-impedance injector support | ✓Included | ✓Included | ✓Included | ✓Included | ✓Included | ✓Included | ✓Included | ✓Included |
| Detachable Cleaning Tank | ×Not included | ×Not included | ×Not included | ×Not included | ×Not included | ×Not included | ✓Included | ✓Included |
| Fuel pumps | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 2 |
Model guide
Use this overview to identify the models you want to compare in detail.
AUTOOL CT150
Four-position standard gasoline injector cleaning and visual testing without ultrasonic cleaning-fluid heating.
AUTOOL CT160
Standard 12 V gasoline injector service with a 2,000 mL ultrasonic tank and heating up to 45 °C.
AUTOOL CT200
Standard 12 V gasoline injector service with six test positions, a 1,700 mL ultrasonic tank, and 3 cleaning / 9 testing functions.
AUTOOL CT400
Six-position service for standard, GDI, EFI, and FSI long injectors with 12 V / 70 V / 120 V selection, a 2,000 mL tank, and a storage drawer.
AUTOOL CT450
Six-position GDI / EFI / FSI service with cleaning-fluid heating up to 50 °C and 10 testing functions.
AUTOOL CT500
Six-position advanced control with 0–40 ms pulse adjustment in 0.1 ms steps, Chinese / English settings, an oil baffle, and 12 testing functions for standard and direct-injection service.
AUTOOL FN606
Combines GDI support, heating up to 50 °C, extended injector-voltage ranges, a detachable 550 mL tank, advanced pulse control, and one fuel pump.
AUTOOL FN608
Extends the detachable heated platform to eight injectors and two fuel pumps while retaining advanced pulse and GDI voltage control.
Manual and support
Manual And Downloads
Download the CT400 manual for setup, injector voltage selection, test functions, cleaning-fluid notes, accessories, and safe operation guidance.

AUTOOL CT400 User Manual
Open the PDF manual for CT400 setup, operation, and maintenance information.

What Is In The Box
What Is In The Box
The packing list image shows the CT400 main unit and included injector testing accessories. Final package contents should follow the package image and current product configuration.
- Main UnitAUTOOL CT400 fuel injector cleaner and tester
- Injector accessoriesAdapter sets, connector parts, sealing rings, and fittings
- Test setupFuel rail, measuring-cylinder parts, signal harnesses, and locking hardware
- Single-injector testingFive plugs are included to seal the unused test positions when testing one injector.
- Fluid handlingFunnel, drain parts, ultrasonic-tank cover, and related fittings
- Documentation and powerUser manual and power cable
Frequently asked questions
Questions And Answers
These answers cover test fluid, cleaning fluid, ultrasonic cleaning, diesel injector limits, GDI voltage selection, single-injector testing, and CT400 comparison with other AUTOOL injector cleaner and tester machines.
Can AUTOOL CT Series Products Clean And Test Diesel Injectors?
AUTOOL CT series products can clean diesel injectors, but they cannot test diesel injectors. If diesel injector testing is required, confirm the correct dedicated equipment before ordering.
How Should I Choose Test Fluid?
Test fluid is used to evaluate fuel injector performance. Use the injector test fluid specified in the product manual to simulate test conditions consistently. For consistent results, use professional automotive injector test fluid. If unavailable, medical alcohol with over 75% alcohol content can be used as an alternative.
How Should I Choose Cleaning Fluid?
Cleaning fluid removes carbon deposits from fuel injectors and is typically corrosive and flammable. For consistent results, use professional ultrasonic cleaning fluid or professional engine carbon cleaning fluid. If unavailable, 75%+ medical alcohol can be used as a substitute, but cleaning performance may vary.
Can I Use Cleaning Fluid To Test Injectors?
No. Cleaning fluid is corrosive and may damage internal machine components, corrode rubber parts, and cause leakage. Use professional injector test fluid for testing. If equipment is damaged because cleaning fluid is used during injector testing, repair costs may need to be borne by the user.
Do I Need To Add Fluid Before Ultrasonic Cleaning?
Yes. Before using the ultrasonic cleaning function, add the professional carbon cleaning fluid first. Do not run the ultrasonic tank dry; doing so may damage the ultrasonic system.
How Do I Set Test Parameters On CT400?
You do not need complicated special settings. Select the function number and set the test time. Select the injector type and test function, then set the required voltage, pressure, time, and pulse parameters.
How Do I Select The Correct Voltage When Testing GDI Injectors?
Select the voltage according to the injector type. If you are unsure, gradually increase the voltage from 12V to 70V to 120V until the injector functions correctly. If the voltage selection is incorrect, there may be no fuel injection or the machine may alarm.
Will The Wrong Voltage Damage A GDI Injector?
Short-term incorrect voltage usually will not immediately damage the injector. However, do not apply incorrect high voltage to an injector for a long time. If the injector does not work properly, adjust to the correct voltage in time.
How Do I Test A Single Injector With CT400?
When testing a single injector, plug the other five cylinders. CT400 comes with five plugs for this purpose.
What Is The Difference Between CT200 And CT400?
CT200 only supports 12V standard fuel injectors. CT400 supports both 12V standard injectors and GDI injectors, making it compatible with a wider range of injector types and vehicles. CT200 does not have dedicated accessory storage, while CT400 includes a drawer for injector adapters and other accessories.
What Is The Difference Between CT400, CT450, And CT500?
Compared with CT400, CT450 adds the Pulse Injection Test. Compared with CT450, CT500 further adds Wide Pulse Injection Test and Continuous Injection Test for more advanced injector testing. For cleaning, CT450 features ultrasonic cleaning with heating up to 50°C, while CT400 and CT500 do not have a heating function.
What Is The Difference Between FN608 And FN606?
FN608 supports testing for 8 cylinders, while FN606 supports testing for 6 cylinders. FN608 is equipped with two independent fuel pumps, each corresponding to a separate left or right fuel rail. If one pump fails, only the corresponding rail is affected while the other side can continue working. FN606 has a single fuel pump, so if that pump fails, the whole system stops working until the pump is replaced.
What Is The Difference Between FN608 And CT500?
FN608 supports 8-cylinder testing, while CT500 supports 6-cylinder testing. FN608 has a heating cleaning tank that can maintain up to 50°C, while CT500 does not support heating. FN608 supports 12V, 12-70V, and 120-180V voltage ranges, while CT500 supports 12V, 70V, and 120V. FN608 also has a cleaning tank that can be used independently or together with the main unit, plus two independent fuel pumps. CT500 has an integrated cleaning tank and one fuel pump.
What Is The Difference Between CT150, CT160, And CT200?
CT150 and CT160 are designed for cleaning and testing fuel injectors of 4-cylinder gasoline engines. The main difference is that CT160 is equipped with an ultrasonic heating function, while CT150 does not have this feature. Compared with CT150, CT200 adds two additional test positions for up to six injectors at once, while the other functions remain similar. Choose CT160 when you need to clean and test up to four compatible standard 12 V gasoline injectors. For GDI high-pressure injectors, compare CT400, CT450, CT500, FN606, and FN608 by supported injector type and test features.
How Long Is The Warranty?
AUTOOL covers the main unit with a 3-year limited warranty and standard bundled accessories with a 1-year limited warranty from the date of receipt. See the Warranty Policy for coverage, exclusions, claim requirements, and any product-specific terms.



























Randy Wagnon Jr. ✓ Verified Purchase –
Excited to try it.
Arrives quick, packaged well! Just wish it would have come with the recommended solvent/cleaner or atleast a sample of cleaner.
Randy ✓ Verified Purchase –
Excited to try it.
Arrives quick, packaged well! Just wish it would have come with the recommended solvent/cleaner or atleast a sample of cleaner.
Luis ✓ Verified Purchase –
Works very well
All types of injectors can be tested, and cleaning is very simple