EGTS measure the temperature in the exhaust pipe. Installed at different positions along the exhaust pipe, the EGTS are used to gather information that is sent to the engine control system (ECU) to ensure protection against overheating and to observe the diesel particle filter (DPF) cleaning.
EGTS are used to monitor the optimum operating point, to protect the relevant components from temperature overload and to keep them in the desired temperature range for optimal conversion rates. EGTS are therefore an important component for the reduction of harmful emissions from vehicles.
EGTS serve as a temperature monitor for turbochargers, catalytic converters, diesel particle filters and nitrogen oxide reduction systems. There are two types of EGTS: Positive Temperature Coefficient (PTC) and Negative Temperature Coefficient (NTC). Resistance in PTC sensors increases with rising temperature, while with NTC sensors, resistance decreases with increasing temperature.
First the EGTS has to be disconnected from the ECU. Then the EGTS has to be connected to a multimeter (in ‘Ohms’ setting) or better still, an oscilloscope. The sensor should then be heated up by running the engine (remember: for NTC sensors, resistance drops with rising temperature; for PTC sensors, the resistance rises with the temperature). Measurement should be taken from the beginning as sensors respond extremely quickly and attention should be paid to see if the resistance drops (or rises) continually (without interruption) with rising temperature. If the sensor is uninstalled, a heating fan can be used to warm it up, while ensuring that the correct measuring range is chosen. Otherwise an ‘open line’ may be displayed, even if the sensor is functioning properly. See question 8 for the correct functioning temperatures of each type of EGTS. The use of caution is advised when working with hot parts and/or when the engine is running.
‘p2033’ is a diagnostic trouble code that informs that the EGTS – located in the upstream pipe forward of the catalytic converter circuit – has a high voltage condition. This EGTS performs the role of protecting the catalytic converter from excessive heat damage.
EGTS can be found either upstream or downstream of: 1) the catalytic converter, 2) the turbocharger, or 3) the DPF. EGTS are also used in the components of the NOX reduction system.
If there has been a build-up of contaminants on the sensor, it may be possible to clean it. This can be performed with a dry cloth.
If an EGTS is faulty, the ‘check engine’ light will be triggered by the ECU. Symptoms of a faulty EGTS include reduced fuel efficiency, failure of other components as well as unsuccessful DPF generation, which can damage the DPF as a consequence.
A properly functioning NTC (Negative Temperature Coefficient) ‘E-Type’ EGTS should display a normal operating temperature range of between 40//+900°C and a resistance between approx. 100 ohm - 200 kiloohm. At room temperature (20°C) it should give a reading of approx. 20 kiloohm.
A properly functioning NTC ‘C-Type’ EGTS has a normal operating temperature range of between 100//+900°C and a resistance between approx. 100 ohm - 200 kiloohm. At room temperature (20°C) it should give a reading of approx. 6 Megaohm.
The difference between ‘E-Type’ and ‘C-Type’ EGTS are mainly their measuring elements. They are identified through the presence of the letters ‘E’ and ‘C’ in the part numbers.
A properly functioning PTC (Positive Temperature Coefficient) EGTS temperature detection range is from -70//+900°C. At room temperature (20°C) it should give a reading of approx. 220 ohm.
You asked Google & NGK SPARK PLUG answers! - Part 7: EGR valves - October 2022
Andy Assmann: Carving out a living as a chainsaw artist - September 2022
You asked Google & NGK SPARK PLUG answers! - Part 6: Exhaust gas temperatur sensors (EGTS) - August 2022
You asked Google & NGK SPARK PLUG answers! – Part 5: Oxygen sensors - June 2022
First NGK SPARK PLUG eSports cup won by German high school student - June 2022
You asked Google & NGK SPARK PLUG answers! – Part 4: Ignition coils, leads & caps - April 2022
The road trip series – Part 4: A family trip through the south of Spain in a Porsche 968 - December 2021
You asked Google & NGK SPARK PLUG answers! – Part 2: Spark plugs - November 2021
You asked Google & NGK SPARK PLUG answers! – Part 1: Spark plugs - October 2021
‘WELL DRIVEN’ by James Ford: My top five diesel-powered vehicles - September 2021
The road trip series – Part 3: The Benelux region explored in a classic BMW M3 and Renault 5 - August 2021
Lee Stone - The multiple freestyle jet sport world champion with the world at his feet - July 2021
Ahmad Daham’s record-setting journey to the top of the drifting world - November 2020
Your car, your story – Part 4: The VW T3 - The last real Bulli - October 2020
“Trust in yourself, work hard and make it happen” – François Lemariey on how to manage a successful MXGP team - October 2020
Your car, your story – Part 3: The Renault Dauphine: The prettiest little four-seater in the world - August 2020
Evergreen Christopher Campbell excited about competing in upcoming GT4 season - July 2020
Your car, your story – Part 2: The Volkswagen Bug, everybody’s darling - June 2020
Dashing through the snow: All you need to know about snowmobiles before winter hits - December 2019
Among the best in the world: Moto2 rookie Lukas Tulovic trusts ignition from NGK SPARK PLUG - September 2019
One piece of a living legend: Win Valentino Rossi's helmet! - September 2019
How to overcome 'the invisible wall': Intercultural training opens up new perspectives in Japanese-European business exchange - August 2019
From chainsaw to forklifts: Spark plugs power far more than you thought - July 2019
Glow Plugs: The exhaust system heroes... And why a summer service is key - June 2019
Throttle up an engine with a click of a mouse - November 2018
Marc Márquez chasing records with NGK - October 2018
Damien Germès: Strong leadership in a changing market - September 2018
NGK at Automechanika 2018 - September 2018
For us it’s all about the engine - August 2018
#ngkroyals - July 2018
But don‘t worry: Moving forward doesn‘t mean we‘re leaving our heritage and quality standards behind.
Our new company name ‘Niterra’ expresses the Group’s desire to be a company that not only contributes to a sustainable society, but also one that makes the earth shine.
The iconic brands - NGK and NTK - have built up highly impressive levels of brand loyalty and will therefore continue to exist for the company’s respective ignition and sensor businesses.
Get to know all about our new company name and what our future vision looks like:A new beginning