Clattery when cold
Join Date: Feb 2012
Location: United Kingdom
County: Greater London
Yes, de-flapping = remove the flaps, spindles, plastic bearings, and rack and pinion mechanism for operating the flaps.
The blanking bushes are for the earlier all-metal Pierburg manifold, as de-flapping those leaves large (12 or 15mm, depending on type) holes in the top of the inlets that have to be plugged. De-flapping the Magneti Marelli plastic/metal manifold leaves 4x 8mm holes on the underside of the manifold, beneath the flat plastic cover over the rack and pinion mechanism. There are no kits for those, but there is no need for one, they look very easy to tap and fill with a bolt sealed with threadlock.
Provided you reinstate and reconnect the actuator motor, the ECU will be happy that it is controlling the flaps even though all it's doing is rotating the actuator spindle. No mapping is necessary.
However it makes sense to blank the EGR off at the same time, to eliminate soot being fed into the manifold. That does require re-mapping to avoid error codes even if the EGR itself remains electrically connected as the MAP sensor detects the missing exhaust gas as an EGR fault. From talking to Autolusso, blanking the EGR and mapping it out costs £150. For £300 you get a full remap incl. EGR blanking that will take a 150bhp CF4 to ~180bhp. There are many other companies including some who will come to you, who will map out the EGR or install more extensive maps, more cheaply, but caveat emptor - many will simply be flogging generic maps they've sourced from GOK where. Some will be excellent and expert, others will be take the money and run cowboys. I'd go on recommendation, if AL is too far away ask in these forums.
As far as DIY is concerned the internet is awash with maps of unknown provenance and mostly pirated software for DIY'ers off virus-laden websites, and you only need a £10 cable from eBay to use this stuff to write to the ECU. But having looked at all that, 1% of people know what they're doing, and 99% cause themselves problems ranging from wasting hours trying to get hooky software to do stuff they don't understand, through to bricking their ECU or trashing their engine. Like all hacking, it's a lot easier to be clever enough to wreck things than improve them. I am taking Clint Eastwood's advice here: "a man has to know his limitations". It's going to be a while before I need to think about maps or can afford one, given the expanding list of mechanical misfortune I'm dealing with, but I intend to get the car into a state where it has a long reliable life ahead. DIY mechanicals I can manage. DIY mapping, too many unknowns for me.
Alternatively, fitting a 4-hole restrictor plate to the EGR will cut down the soot to an extent and avoids the need for remapping. A 4 hole plate is now a Fiat recommendation. In the short term I see no problem with that.
However the consensus seems to be that the reduction of low-rev efficiency (due to swirl flap removal), is noticeable if EGR is retained or restricted, but not if EGR is blanked and mapped out. EGR is intended to reduce NO emissions by lowering combustion temperatures thanks to feeding low-oxygen exhaust gas into the inlet, ie deliberately impairing the fuel efficiency of the motor. Blanking the EGR makes the engine more fuel efficient at the cost of some increase in nitrogen oxides, but none of these options appear to affect current MOT emissions testing outcomes.