So much stuff replaced, same problem

[chris_Mk3Annivers]

Hi

Ive a Mk3 2.0 16v Anniversary, Eng ABF

My problem is intermittent stuttering, somedays it drives like a dream and others it stutters like a pig namely between 3 and 4k and lacks power, below is what ive had replaced, problem still there, any thoughts..??

Cam Belt
Crank Pin Sensor
Rotor Arm
Coil Module
Ingnition Coil
Lambda Sensor
Ignition Leads
Spark Plugs
Fuel Filter
Dizzy Cap

On the days it drives like a dream i can average 40.2mpg over 30 miles
On a pig day it averages a little bit less

Air Mass Meter not fitted on ABF

Thanks for your ideas 

[monkeyalan]

fuel pump and ecu relays. clean out the throttle body and oil breather pipes.

[AudiA8Quattro]

As above , those relays.