My a4 has started throwing  too lean error

Has got worse over time, now getting dead patches as I accelerate until turbo cuts in.

Has anyone an idea what to check for?

 

Is it worth you checking the maf, lambda sensor and coil packs/spark plugs first. 

I have done the suggested checks and cleaned the MAF with contact cleaner.

Now runs more smoothly but still showing same error. This happens miles after the engine reaches operating temperature.

I haven't found any leaking air pipes so far. Is there anything that is temperature sensitive?

Could there be an issue with leaking boost pipes? 

I have just started getting the same issue with my 2007 cabriolet. 
 

I installed a new MAF and the engine still “pulses” on cold idle and throws up the running lean issue. Exhaust starts popping and there is a “thud” sound from the air intake.

However, if i unplug the MAF, the car idles perfect and the pulsing, thuds and pops disappear????

At the moment I am running the car without the MAF plugged in until i can figure out why it doesn't work with a new MAF installed.

 

Would be interested to see how yours runs if you unplugged the MAF? 
 

Following this tread to hopefully find some answers.