PID 5D°
Fuel injection timing
Fuel injection timing — how far before top dead centre the unit starts delivering fuel. It drifts on poor fuel, with clogged injectors and with a tired crankshaft sensor. Do not confuse it with ignition timing advance (PID 0E): that one is about the spark, this one about delivery; a diesel has no ignition timing at all but does have injection timing.
What is normal
A steady departure from the commanded value means injectors, rail pressure or the crankshaft sensor.
These figures hold for most cars, but the maker has the last word: some engines run hotter or idle higher by design.
How it feels behind the wheel
The same fault shows itself in different ways. Each sign below says what to look at in the live data.
The engine stumblesThe engine runs unevenly, the car shakes at idle, the exhaust note stutters. On the move the pull sags and consumption rises.It jerks under accelerationAt steady throttle everything is fine, but under acceleration the car jerks or hesitates, as if the pedal was released for a moment.Smoke from the exhaustVisible smoke from the tailpipe. The colour is the clue: white, blue and black mean entirely different things.
How to see it
In CarScan: the Live data tab, «Start polling». The app asks the car several times per second, draws a graph and remembers the highest and lowest value of the trip.