If you’re looking to take measurements and carry out vehicle emissions tests with the Hofmann geogas 5000 emissions analyser, its software makes the process quick and simple to save time and boost productivity in your workshop.
We have already taken a look at how to perform a petrol MOT test (BET) with the geogas 5000 so now let’s run through the steps required for diesel MOT testing.
Select the MOT menu from the software’s home scree, choose the Diesel Test option, then at the next screen enter the vehicle’s registration number and click on Continue before choosing the type of engine – turbo or non-turbo – being tested.
Continue once more, select the vehicle class and how the oil temperature is to be measured, and then whether RPM measurement is required. This is recommended for new vehicles.
After advancing to the next screen you will be instructed to ensure that the vehicle is running at a steady RPM and to connect the EOBD device to the vehicle’s 16-pin socket. Doing so and confirming triggers the wireless communication between the vehicle and the geogas 5000.
Select the time period in which the vehicle was first registered then at the next stage there will be six DVSA-mandated checks for you to carry out:
- Sufficient oil in engine
- Oil pressure is not too low
- Camshaft belt is in a satisfactory condition
- No abnormal engine noise
- The governor has not been tampered with
- Engine is at normal operating temperature
Once you have confirmed these, allow the engine temperature measurement screen to show that the engine is up to temperature – the gauge will turn from red to green to demonstrate that it is good.
Confirm that the engine’s idle speed is correct then bypass the cut-off measurement as that is not required under UK legislation.
Press the Confirm button but do not put the sample probe in the exhaust pipe until zero calibration of the smoke meter has taken place.
At that point you can insert the probe but be sure to position the smoke head away from a potential smoke bloom from the exhaust, ensuring that results will not be contaminated.
How to calculate diesel emissions results during an MOT test
Confirm that the probe is in place and then the geogas 5000 will start a ten-second countdown so be ready at the end of that to press the accelerator pedal to the full governed speed – push it down fully in less than one second, taking care to do it quickly and continuously but not violently.
Once the engine has met the governed speed, release the accelerator. The results will then be calculated.
Remove the probe from the exhaust pipe and dock it back on the workstation along with the smoke meter, then press Confirm to start the zero drift check.
That will trigger once you have pressed the Confirm button so allow the system to complete the check, then at the next screen ensure you unplug the EOBD device from the vehicle as instructed.
The test will now be complete so after pressing OK you can select the name of the tester, add in any comments beneath the results if required, and print out the results.