backfiring in intake after flap delete

[MK06]

Hello everyone
So I recently DIY'ed the intake manifold flap delete.
For some reason, the car now backfires like crazy in the intake on every cold start but settles down once it warms up and the revs go down.
The car is bone stock and hasn't been flashed before. I don't have any CEL on the dash.

Has anyone else also experienced this?
Also, can it cause any damage of some sort?

[TrevoRS4]

Mine will sputter a bit as I get past half throttle or so. Only when cold. It’s more significant now with the cold weather versus when I had it deflapped over the summer.

[MK06]

@TrevoRS4 Mine backfires (sounds like popcorn popping) continuously in the intake on every cold start. When doing the deflap, do you remove only the flaps on the intake or do you remove the dividers in the port as well?

[TrevoRS4]

Removed both the flaps and dividers

[MK06]

Thanks bud, mine also has both the flaps and dividers removed so I'm not sure where the problem might be. I'm starting to think that a flash is necessary, has your vehicle been flashed bud?

[mojoe]

was thinking about removing mine,when I did a carbon clean. Phoned MRC first,they said " your car will go into limp mode,and you will need a £600 remap ".
So I left them in

[MK06]

My car runs completely normal, no limp mode or CEL at all. I just removed the flaps and left the shaft in place. The only thing is the dreaded backfiring on every cold start. It doesn't seem like a common problem after the flap delete. I might consider putting the flaps back in to solve the issue.

[Grandadg90]

Best bet is to deflated the manifold, remove the pre-cats and have the car mapped. Rob from Nicholson motors(Doncaster), who knows his RS's really well will map it for way less than £600. I had mine done, hugh difference.

[MK06]

Thank you @Grandadg90, I will consider that.