Hi all. I'm after some help. My superb is running slightly lumpy at idle. Not missing more hunting. Sometimes there is a slight hesitate on acceleration too. I've replaced the clutch and dual mass. Ecu temperature sensor. Injector wiring. And maf sensor. As well as all the usual service items. I'm scratching my head here. Anyone have any ideas as to what can cause this

1.9? Wiring loom for injectors? Get someone to plug in VcDS and see injector to injector adjustment values.

Hi sorry. Yeah it's a 1.9tdi awx. I changed the loom to the injectors. I also noticed it seems to be much better with the a/c on. As if the extra load on the engine increases the rpm slightly and stops the lumpy idle

As stated get it scanned.

 

It could be the EGR valve jammed with gunk and not closing properly which would affect idle. 

 

The ECU detects load on the engine and adjusts fueling accordingly so putting the A/C on will make a difference as you are experiencing.

I've cleaned the egr valve. That's not gunned up