missfire low rpm only, ht leads,coil pack, plugs all replace

[mk5 polo]

Hey hoping for some pointers with this.

FAULT = misfire at low rpm below 2000 only, when idle every 10 seconds or so the revs will drop slightly but not enough to cut out

PARTS REPLACED = coil pack, ht leads, spark plugs, all so sprayed wd40 directly into carb at full throttle. Also removed and cleaned a sensor a side of throttle body (not sure exact name)

HISTORY = when fault started got a diagnostics check indicating a misfire on banks 2 & 3 and was advised to replace coil pack, fault persisted and eventually replaced all likely parts. The fault initially was bad enough for the car to go into limp mode but not now.

Thanks in advance

[alexperkins]

hmm could be many things. can you get a vagcom scan done and get the proper error codes?

[mk5 polo]

HI Alex

I do not have access to the error codes anymore it was done by a shop, when the device was plugged in they only indicated a missfire,

Thanks

[mk5 polo]

Little update

I removed and cleaned all my spark plugs with a wire brush, they where black and covered in carbon, this could cause the missfire and suggests the car is running rich. How would you lean it out or is there a better way other than leaning it out?

Thanks

[alexperkins]

Lambda controls the fuel supply mate so you might want to get that checked