14/09/2026
Vauxall Mokka
👉DPF CLEAN
👉AMBIENT TEMPERATURE SENSOR
Customer enquired about getting their dpf cleaned as a warning had come up on their vehicle for blocked dpf.
We always run a diagnostic check first.
Codes came for ambient air temperature sensor and also for turbo underboost performance.
While many people dont realise, when the ambient air temperature is faulty, a car wont do a regen because the ecu is confused with the outside temperature as it needs a specific range to work in, it will prevent any regens to stop potential thermal damage.
This will cause the dpf to block up as there are no regens being done.
But a lot of people will ignore that ambient temperature fault thinking its totally unrelated.
For the turbo underboost we did a smoke test to make sure no air leaks. There was none.
That specific code also comes up if the MAP sensor on intake manifold is clogged up with soot.
We took the MAP sensor off and found the culprit. Totally caked in soot so the sensor was not able to read the data causing the underboost issue.
Cleaned the map sensor. Replaced the ambient air temperature (unfortunately took no pics of that) and did a dpf clean.
Was one of the most blocked we have seen. (The picture shows how black the foam was with soot. Also before we get comments on look at it all over the floor, we rinsed it off with water, and it was on the customers property and she didnt mind.
Once all the black smoke had gone down, we did a static regen to make sure the car would be able to complete future regens. It completed it and all the values were where they should be.
We recommended the customer get a carbon clean for the intake manifold in the near future.
Now the car no longer runs sluggish and no dpf warning. All good.
And it was a tiny little ambient temperature sensor that had caused all this.
If you have dpf issues and are struggling to get it clean. Drop us a message or give us a call.
Streetside Auto Repair
