Testo 340 Portable Combustion Analyzer

340 Combustion Tuning & Analyzer Engine Kit

The testo 340, for maintenance and tuning on both rich-burn and lean-burn engines, is the ultimate instrument in portable combustion tuning. The 340 provides you with the information you need to make the best decisions when it comes to combustion analysis. It's the ideal tool to confirm proper set-up and to identify emission problems before they get serious.

Stationary engine exhaust, when uncontrolled, can have very wide concentration ranges. As a result, both CO and NO can fluctuate significantly. This unit measures both gases for a perfect rich-burn engine set-up. The on-board dilution system and the replaceable interference filters both keep the sensors secure and your readings accurate. Analyzer diagnostics will display the filter lifetime in ppm hours to inform you of filter change-out, which is quick and easy. The process increases accuracy and extends sensor lifetime.

To improve sensor protection, the 340 is built to measure high concentration with its unique, automatic 5X dilution system. When the concentration set-point is reached, precise amounts of dilution air are added thereby lowering the concentration applied to the sensor. The analyzer will automatically compute and display the correct values.

Take a look below at some of the great features offered with the new testo 340:

• 4-gas flexibility (O2 plus 3 more) in a rugged, compact hand-held design.

• Automatic dilution extends range of CO sensor to 5X, or swap in another toxic sensor.

• For more flexibility, the "Dilution Overall" option extends the range of all sensors by a factor of 2.

• Easy to read, back-lit display. Use simple function keys to navigate throughout the menu.

• Rubberized shock-resistant housing with integrated magnets for hands-free operation.

• Calculation of: CO2, efficiency, excess air, mass emissions (with pitot tube).

• Designed for simple, fast operation and constructed for demanding daily rugged use.

• Optional infrared printing to produce hard-copies of your tuning and calibration records.

• Integrated pressure sensor measures draft or differential pressure, exhaust gas and flow velocity.

• 18 fuels to choose from, plus 10 user-defined fuels (using input from EasyEmissions software).

• Onboard diagnostics: simply go to the diagnostics screen to see your instrument status.

• Transmit data via bluetooth.

340 Portable Combustion Tuner Accessories, Upgrades & Replacements


• BLUETOOTH OPTION: On new orders only, no upgrade later

• UPGRADE SENSORS: COLOW, NOLOW, NO2, SO2, NOHIGH, 2X Dilution (over-all sensors)

• INFRARED PRINTER: with optional printer paper

• SOFTWARE: EasyEmission software with USB cable


• PITOT TUBES: "L" type, 13", 1112°F (no thermocouple), or "Straight" type, 13", 1832°F (w / TC)

• OTHER: Hi-temp. probe tube shafts, extension hoses & filters (see literature for details)

Additional Information:

Testo 340 Portable Combustion Analyzer Sales Brochure (pdf)

Click here to download a copy



Testo 340 Portable Combustion Analyzer Instruction Manual (pdf)

Manual is being revised and updated. Download will be available soon.



Testo 340: Standard Kit Features & Accessories List (pdf)

Click here to download a copy.

Learn more in the Testo Video Library.


The Testo 340 Combustion Analyzer is not currently available in the MurCal web store. Please contact the inside sales department for availability, price quote and lead time.