Viewing 40 posts - 1 through 40 (of 62 total)
  • Whats a "Swirl Flap"?
  • Wozza
    Free Member

    The car put itself in safe mode today, at 55mph in the outside lane, no power steering, no servo brakes and about 2 bhp, which was “interesting”. The AA guy said it’s my swirl flaps and something to do with the inlet manifold, but nobody can explain what it actually does.

    So out of curiosity can anybody help? Why did the car shut down? How did it know? What the hell does a swirl flap do?

    It’s a BMW 330d

    Cheers

    BigJohn
    Full Member

    It controls the foo foo valve.

    paulosoxo
    Free Member

    BigJohn – Member

    It controls the foo foo valve.

    Don’t you mea the Wah-wah socket?

    http://lmgtfy.com/?q=http%3A%2F%2Fwww.swirlflaps.co.uk%2F

    🙂

    scaredypants
    Full Member

    nasty – leads to sludging of the wiffle pits

    thepurist
    Full Member

    I thought they were to damp the air flow after SurfMatt’s flounce.

    motivforz
    Free Member

    Their proper name is tumble flaps, looking at those google results it seems BMW have decided to rename them, because they can. They are inside the inlet manifold and are a valve/flap which directs the airflow to the actual inlet valves, with a profiled runner to introduce tumble/swirl of the airflow, promoting better mixing of the air fuel mixture, and so better combustion.

    mboy
    Free Member

    The more agitated the air going into your engine’s cylinders is, the more complete the burn is, and hence it is more efficient and powerful for a given amount of fuel.

    Some newer cars have “swirl flaps” in the intake manifold, these are there to introduce more turbulence to the incoming air in order to promote a better burn.

    costello
    Free Member

    mmmmm not good news i’m afraid ,this is very common on bmw d engines,hopefully it won’t have done any serious damage,the good news is you can have the swirl flaps blanked over /removed,it will never happen again and it won’t effect your engines performance,
    “why are they fitted then?” is a logical question at this point and i can only say it’s an e.u emmisions thingybob but your d will get on very well without them.

    anthonyb
    Free Member

    Thats bad news im afraid. Sounds like the emergency engine management kicked in, due to an engine problem. And if it is indeed a swirlflap failure, the prospect isnt great.

    I use to own a 320d touring, and after a few nightmare stories from other owners I had my swirl flaps replaced with blanking plates.

    The swirl flaps basically sit at the entrance to the manifold, and rotate back and forth,(not sure of there exact purpose, but believe they are there to help fuel management when idleing. There was no negative impact in the total removal of mine.

    Anyhow the flaps have a tendancy on e46 models and earlier, to corrode, break loose, drop into the manifold, and at worst totally wreck your engine cylinders. Which, according to many angry owners reports, results in exactly what you experienced. Ie, no power etc.

    Id get it down the dealers/decent independant straight away if you can. It will be easy to see if theres been a swirl flap failure. Literally a 5min job to check.

    Good luck!

    The garage that removed mine said they had another 4 bmws booked in that week for the same removal process.

    Wozza
    Free Member

    Cheers for the replies, it’s good to know exactly what they’re talking about!

    But the plot thickens… it would appear that my car has had the flaps already removed! Weird, anyway, it’s still at the menders with the engine all over the floor.

    Kato
    Full Member

    I’ve just today had the swirl flaps out of my 320cd and PMW blanks put in their place. 320d before 2004 were rife with problems with the screws that secure the flap to the are failing and flap disappearing down the inlet manifold resulting in the the engine going bang. Later models had one piece flaps which cured this

    TimS
    Free Member

    I had the flaps out of my 320d last summer and replaced with screws/epoxy. As I was removing the last one from the manifold, it literally came apart in my hands. Lucky escape 😯

    jj55
    Full Member

    The giggling pin has fallen off the laughing shaft 😯

    leffeboy
    Full Member

    They are the tonsils of car world aren’t they?

    molgrips
    Free Member

    Aren’t they for increasing EGR? Which reduces harmful emissions. Not like that matters to BMW drivers, that would mean giving a sh*t about someone else 🙂

    bakey
    Full Member

    Get a BMW independent to blank off the EGR, remove the DPF and get it remapped to delete the regen. More power, more mpg and a whole lot less to go wrong…

    resisted
    Free Member

    similar question; is it the same situation with i engines too? I have a 116i and recently the emissions light came on and even after service/MOT it’s still there. I happen to drink with the service manager for a large BM dealership and he says “it’ll be crappy supermarket fuels you put in it you pikey bastard” (or words to that effect). Basically was told to ignore it as it is there to indicate if you were likely to fail a continental emmissions check.

    but I still feel I ought to be worried. should I?

    molgrips
    Free Member

    Get a BMW independent to blank off the EGR, remove the DPF and get it remapped to delete the regen. More power, more mpg and a whole lot less to go wrong and more soot and nasty pollutants to mess up the air quality and cause health problems

    FTFY.

    Wozza
    Free Member

    So after the best part of 10 days down the garage they say it’s the “high pressure diesel pump”. At 1500rpm it just gives up and cuts the engine out.

    molgrips
    Free Member

    That sounds expensive.

    bigyinn
    Free Member

    resisted, take your car and cane the absolute pants off it, really rag it. Should help shift the engine scoot etc, gets the cat nice and hot too.
    *I accept no liability if ANYTHING bad happens as a direct result of the above*

    molgrips
    Free Member

    My Passat is majorly improved by half an hour driving at 100mph 🙂

    Wozza
    Free Member

    That sounds expensive.

    Is pretty much what I say everytime i’m at the garage!

    take your car and cane the absolute pants off it, really rag it. Should help shift the engine scoot etc, gets the cat nice and hot too.

    I do a lot of long motorway miles, will that get it hot enough or are we talking “drive it like you stole it” territory to see an improvement?

    bakey
    Full Member

    Get a BMW independent to blank off the EGR, remove the DPF and get it remapped to delete the regen. More power, more mpg and a whole lot less to go wrong and more soot and nasty pollutants to mess up the air quality and cause health problems

    FTFY.

    Here’s the key: ‘more mpg’ ergo less emissions per mile…

    Further, it’s the tiny particles which cause the most harm, not the larger sooty ones (although I agree they’re not benign); a DPF does not remove the tiny particulate. A diesel running a DPF tends to increase CO2 emissions; don’t also ignore the environmental / energy cost in maunfacturing the damn things in the first instance.

    HTH

    molgrips
    Free Member

    Shouldn’t have the issues if you do lots of long motorway miles tbh but a ragging (aka the Italian Tune-up) will always help. Try driving at 80mph in 3rd/4th for 5 or 10 minutes (but don’t redline it for that long)

    molgrips
    Free Member

    I’m aware of the disadvantages of DPF and EGR. But overall particulates are much reduced with a DPF which coutners a slight increase in consumption I reckon. And what about NOx?

    bakey
    Full Member

    A DPF has an insignificant effect on NOx emissions. More fuel, higher NOx.

    Wozza
    Free Member

    aka the Italian Tune-up

    LOL, added to vocabulary.

    resisted
    Free Member

    resisted, take your car and cane the absolute pants off it, really rag it. Should help shift the engine scoot etc, gets the cat nice and hot too.
    *I accept no liability if ANYTHING bad happens as a direct result of the above*

    It doesn’t really do much caning tbh, it’s only a 1.6 and it weighs about 4 billion tonnes, and it looks like a canal barge. Just trying to figure out why the **** we bought it actually!

    molgrips
    Free Member

    A DPF has an insignificant effect on NOx emissions. More fuel, higher NOx.

    Yar, I’m talking about EGR – this is a NOx reduction thing.

    PeterPoddy
    Free Member

    aka the Italian Tune-up

    It’s a well known phenomenon and does actually work. Obviously Italian vehicles benefit the most, but it applies to all.

    Engines need revving from time to time. Keeps them sweet.

    Story time:
    I bought a brand new Ducati Monster 696 a few years ago, brand new model, first batch in the country. On picking it up it rode like a dog, snatchy and crude, so I rode it straight back again. 6 miles on the clock. Long story short but it was a fuel injection problem they fixed in an hour or so, and the bike was better. But not perfect. Still hunted on a steady throttle, so I took it back again. They checked it over and declared everything perfect, but the mechanic took it out for a ride to ‘put the engine under load’
    He came back 1/2hr or so later and said he thought I’d been to gentle running it in, and that coupled with the earlier FI problem had probably left deposits on the sensors. He just said “If it happens again, thrash it. Lots!”
    “Ahh” says the manager “the Italian tune up!”

    And it worked. That bike ALWAYS felt better after a right good pasting: And I’m talking rev limiter in every gear, up and down the box, slow and fast, for as long as you can get away with it….. 🙂

    speed12
    Free Member

    The EGR valve is the main way of bringing NOx down (unless you have an SCR fitted which little to no passenger cars currently do). Blanking off the EGR valve will have a very good effect on CO2 (and therefore fuel consumption) reduction, but the NOx will go through the roof as they are on a very very steep tradeoff curve.

    xiphon
    Free Member

    While your beemers in the garage, can you ask them to fix your indicators? thanks.

    speed12
    Free Member

    A diesel running a DPF tends to increase CO2 emissions; don’t also ignore the environmental / energy cost in maunfacturing the damn things in the first instance

    A DPF won’t increase the C02 per se. During regen it will (to a small or greater extent depending on how good the regen calibration is) but during normal running you should see near zero effect. Also, in removing the DPF, unless you have the whole calibration remapped, then you have just removed a massive lump of backpressure in the exhaust which the engine was calibrated with so your potentially going to upset quite a bit of the cal (can actually lose torque etc). A decent calibrated engine will see very very very minimal performance loss from a DPF.

    mogrim
    Full Member

    While your beemers in the garage, can you ask them to fix your indicators? thanks.

    Drove a BMW yesterday for the first time ever, weird indicators – I can confirm they do exist, but they don’t work like every other car I’ve ever driven.

    molgrips
    Free Member

    How much does EGR affect fuel consumption though, really? It’s just replacing some of the air in the cylinder with exhaust, but most of that air you don’t need anyway when cruising…?

    Speed12 – VW TDIs in the USA have a system for scrubbing NOx – could be similar to SCR.

    HoratioHufnagel
    Free Member

    Will an “italian tune-up” actually help with a sooted up or corroded inlet manifold? Its just air flowing through there and i doubt that would be strong enough to remove the soot.

    My car had an engine rebuild for other reasons and i took the opportunity to replace the manifold with swirl flaps for the latest redesigned version. The soot caked on the inside is pretty solid.

    (like this (not mine))

    The EGR valve only recirculates the exhaust gas at partial throttle, which is what gradually clogs up the inlet manifold, so blocking it off or removing it via a remap should help too.

    molgrips
    Free Member

    I would say that keeping it clean and tidy inside by a periodic thrashing would help prevent that happening.. but perhaps not fix it. Although on my old Passat the exhaust would’ve been very hot at the EGR valve cos the pipe was really short, so it might’ve helped. It was a slow car so got thrashed a lot to make progress, and the EGR was clean as a slightly grubby whistle inside when I removed it because everyone was telling me it’d be gummed up.

    But then you are right it only works at partial throttle.. perhaps on my car then the throttle you needed to drive at 70mph was enough to switch off EGR 🙂

    Wozza
    Free Member

    They say they’ve given it a thorough cleaning out at the inlet end so hoping that it’ll run a bit sweeter and be a little better on fuel.

    xiphon – Member
    While your beemers in the garage, can you ask them to fix your indicators? thanks.

    In my defence I reckon Audi drivers are the worst.

    resisted
    Free Member

    My vote goes to merc drivers, usually the dimentia setting in C + E class drivers causes them to forget to indicate, likewise the constant re-plastering of lipstick and chatting to gal pals of CLK and SLK drivers distracts them far too easily.

Viewing 40 posts - 1 through 40 (of 62 total)

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