I have a Peugeot 206 hdi on a 55 plate. Engine management light on ran diagnostics code p0401 incidentally sometimes when I accelerate at 2000 rpm get a lag kind of anyone any ideas what to look into. Thanks in advance.
Live data would show any discrepancies between expected measurements and actual measurements. Fault codes are ok as far as telling what has happened to the car, but the live data is much better at explaining why it has happened.
If the EGR is sticking, giving it a clean may free it up. There isn't much else immediately around it that would benefit from a clean.
The fault is not with the actual EGR valve, but the electro valve solenoid which controls it. On the 206 this is at the back of the engine on the bulk head, the solenoid with the blue plug going in to it.