G40 running to much air to fuel..

[dom101]

So last week or so i have noticed the car doesnt seem to be running so well especially when have the foot down, the charger is all fine and boosting properly, however my feul to air ratio is showing just lean and then reads off the dial when i put my foot down or on motorways, it runs fine when no high revs and not putting the foot down.
i have recently changed the lambda and temp sensor as read they are parts that could affect.
Also the exhaust is blowing by the manifold and flexi part since it fell off on the motorway but no big holes but you can here it blowing whilst driving, i have read that this could affect the running but not sure how?
also that it could be an ecu or chip failure?

Never had this befor any idea where to start? just want to get sorted as read that running a car lean can be bad for the engine espcially supercharged cars.

cheers

[PeteG40]

could be fuel pumps...

is it a genuine g40? or a conversion?

[dom101]

Genuine g40 it has in line pump when bought it, anyway you can check? Or change fuel filter?