Exhaust Flaps FAQ

[Shadow6ix]

I couldn't find anywhere this has been asked before, but I was wondering if it's possible to adjust the programming on the ECU to change the behaviour of the exhaust flaps ie. open throughout the rev range in sport mode?

[adsgreen]

No - not unless a third party like MRC have cracked the ECU.

The only other options are to unplug (and plug) the vacuum lines to the flaps - they will remain open at all times then.

Or mess about with the vac or signal lines:
- you could put another solenoid after the OEM one that stops the vacuum and wire this to a different button.
- you could add an override switch to the existing wiring that bypasses the oem ECU signal.

Both PITA so many just unplug the hoses.

[pDkALO]

The only other options are to unplug (and plug) the vacuum lines to the flaps - they will remain open at all times then.

+1

nightmare of a job to do though - took me nearly 10 whole minutes....

[Rigsby1208]

What is the preferred procedure for plugging the vacuum pipes which are removed from the valves

[adsgreen]

What is the preferred procedure for plugging the vacuum pipes which are removed from the valves

suitably sized wood screw.
Or a golf tee (apparently) works too.
Don't forget to tape up the nozzle on the flap actuator - don't want <beep> getting in there.

[pDkALO]

What is the preferred procedure for plugging the vacuum pipes which are removed from the valves

suitably sized wood screw.
Or a golf tee (apparently) works too.
Don't forget to tape up the nozzle on the flap actuator - don't want <beep> getting in there.

This

I also added a dab of sealant to a stainless screw just to be certain (waited for it to go off before running again), and cable tied them up out of the way. The perfect cap for the valve connector is the little silicon thingy that goes on the end of the aerial of radio control cars - pence from a big boys toy shop...

[RS4_Chris]

Quick question here, i've been running with the exhaust flaps disconnected for about 6 months but now im wondering about changing to a Milly. Is there much difference between a std exhaust with the flaps permanently open and the resonated, valved milly? Dont think i have the balls for going non-res yet!!


cheeRS

[adsgreen]

The non res valved with valves closed is still louder than the standard with valves open.
To be fair, it's not massively louder - at 4.5k static test mine clocked 88db valves closed and 98db valves open.

Whichever way you go, the only difference between the non res and res is the centre section which can be removed separately.
So go non res, see if you can deal with it and if not it's not too bad to change.
If you go res first then you'll always be able to sell the res section should you need to.

[neckarsulm]

I wonder if a brake bleed nipple cap would fit the pipe on the diaphragm to protect it when flapper modded
Good news, I used oil rather than spray lube in mine and it works now so great tip thanks!
I pressed the S button numerous times while driving to help free it up even more.

FYI if a car has had a new back box, the old one has to be cut off so there will be a sleeve just before the two pipes meet.
No sleeves = original back boxes.

[adsgreen]

No need to keep pressin the s button
Car will do it for you if you leave it in S mode (remember in gears 3 and below flap open at idle and >4k but closed otherwise).

[brn7y]

Has anyone had the spring return fail as I have worked a stuck flap loose today to the extent I can function with my fingers but it won't return to the open position naturally.

[noMoreRs4]

I've got a stuck flap on the rhs box. I've read this thread and think ill give getting it going with some wd40, proper oil, and a 'nudge'. The only thing im unsure of is where to apply the wd40 and oil. There is the actual flap on the inside of the exhaust, and im guessing a sealed actuator on the outside of the exhaust. Do I apply WD40 and then oil on the inside of the exhaust around the flap or outside around the actuator?

thanks


simon

[WillRS]

Has anyone had the spring return fail as I have worked a stuck flap loose today to the extent I can function with my fingers but it won't return to the open position naturally.

Same here - right hand one was jammed shut initially but I've worked at it for a few months now and it does open when it's supposed to. However sometimes i find it's shut before I start the car whereas the other one is always open when engine is off. Comparing the two the slightly suspect one doesnt appear to have any return spring feel to it whereas the fully working one does so it feels like the spring loading has gone?

[WillRS]

I've got a stuck flap on the rhs box. I've read this thread and think ill give getting it going with some wd40, proper oil, and a 'nudge'. The only thing im unsure of is where to apply the wd40 and oil. There is the actual flap on the inside of the exhaust, and im guessing a sealed actuator on the outside of the exhaust. Do I apply WD40 and then oil on the inside of the exhaust around the flap or outside around the actuator?

thanks


simon

You can use wd40 on the flap on the inside I.e at the mounting points/ pivot points and on the moving parts of the actuator to help free it up but you should then lubricate the moving parts with some decent high temp oil as wd40 whilst handy for getting things unseized will not lubricate the mechanism properly.

[noMoreRs4]

@ WillRS - thanks, ill give it a go.