20/07/2026
The amount of times we've heard "Those diagnostic scanners just tell you what to do!"
The fault codes read by the diagnostic machines are the result of something which has happened within the engine, but not necessarily the cause. We can be tracing back through dozens of fault codes to find the needle in the haystack.
Take this 2021 Range Rover, brought in to us in 'limp' mode with fault codes relating to the EGR valve, and engine inlet pressure faults.
If we went down the route of what the scanners tell us, we would be barking up the wrong tree in the wrong forest, wasting our time and costing the customer money.
After scouring the endless live data graphs for anomalies, we stumbled across the pressure sensor in the exhaust.
The 'before' graph shows a steady rise and fall when revving the engine, and even though the pressure gets up to the correct figure, it takes a long while to get there.
By pressure testing the pipe to the sensor, we found it was blocked, which was confusing the vehicles computers into thinking there was an airflow problem. If the engine can't expel the air through the exhaust, it can't draw it in through the inlet, hence the inlet pressure fault code.
The pipe was cleaned and blown through, and by the second graph, we can confirm the readings are correct, and the fix was a success💪