Issues after installing precision works ignition coils and armaspeed carbon air intake

Hello everyone,

As topic states, having some issues with my BMW M135i N55 EWG with ZF 8 speed gearbox.

Some info of the car

The car used to run stage 2 with catless downpipe and Dorch engineering stage 2 HPFP without issues.

Trouble started after I replaced stock ignition coils (never replaced til 130k km) to precision works ignition coils, NGK sparkplugs and Armaspeed carbon air intake.

Issues:

Idling - I can clearly hear the exhaust note going up and down, however RPM needle does not move.

Hesitation & closed throttle position - from 6th gear - 8th gear, when I WOT from 100km/h or 2500 rpm, the car hesitates, I can clearly hear the air filter spools up then it stops for half a second then back sucking air again, but from this point, the car no longer make any boost and throttle position is at 13.9% even I am flooring it.

Check engine light

Read the error code - it's maf sesnor related and running lean. (Replaced new MAF sensor now)

Things I have done:

- logs - log shows at 6th gear 2500 rpm, once I go full throttle, it hits max targeted boost for half a sec, then boost drops to 150kpa, throttle position closed to 13.9%. AFR 0.9-1 (running lean). Fuel pressure is normal.

- Boost leak free - fixed all the intake pipes and made sure I'm boost leak free.

- Replaced MAF sensor.

- Cleaned vanos solenoid & boost sensor.

- Gearbox torque limiter removed.

1st-5th gear drives fine. No hesitation and no sign of power loss.

Could this be tuning related?

Thanks,

James

Totally unfamiliar with either of those, but a careful check over the vehicle may be in order.

It's easy to miss, or dislodge, a connection or earth when working on modern vehicles.

As it uses a MAF, I would also have a careful look over the new intake for missed hoses, open hose nipples, dislodged gaskets, etc - to the point of using some engine start, or similar product, sprayed around the various gasket and hose areas to see it the engine note changes, which would indicate an air leak that is bypassing the MAF.