swirl flaps

[zagmad]

Anyone know anything about swirl flaps. I appear to have problems with my swirl flaps and wondered what can be done about them. Eg remove or use a better material so they don't break down and ruin my engine.

[Mister Towed]

Swirl flaps = absolute nightmare. I had a Saab 9-3 with the GM 150 diesel engine and a swirl flap broke and dropped into the engine doing £1100 in damage.

There are two different types - plastic flaps that drop off and damage your engine as above, and new, improved, stainless steel ones that drop off and destroy your engine completely.

I swore I'd never risk buying another car with them fitted, but I've just gone and bought an Alfa GT with the same engine. I will be removing the swirl flaps and probably blanking off the EGR valve while I'm at it as soon as possible. I'm hoping to be able to do it myself but there are specialists who can do it - http://www.autolusso.co.uk/swirl-flap.html

Typical symptoms of swirl flap problems are that the car will go into 'limp home' mode and won't rev above a fast idle. It might well clear after being parked up but once you've got the early symptoms it's only a matter of time before the engine cuts out completely and won't start again.

Good luck!

[zagmad]

Thanks that's a great help. I'll try and get them filled. The engine light comes

[zagmad]

Oops engine light cones on but when I hit hi revs the light goes off. Seems to be a problem with most plastic parts folding and flopping

[Mister Towed]

The way I understand it is that the swirl flaps restrict airflow at idle, causing vortices to mix up the fuel and air to smooth out the idle. That works fine when when they're new but...

...they're located inside the inlet manifold on the engine side of the EGR valve, which recirculates burnt exhaust gasses back into the engine for emissions reasons. The soot and partially burned diesel that the EGR valve pumps into the engine over the course of 100,000 or so miles (during warm up?) gums up the swirl flaps and makes them stick in their closed position.

This restricts the airflow into the engine so it won't rev, and because the electric motor that's trying to turn the shaft they're mounted on is quite torquey, if the flaps don't unstick the two part shaft distorts allowing one or more of the flaps to drop out and get sucked into the intake ports.

The plastic ones make a mess inside the intake port but the metal ones can jam a valve open which the piston will strike on its way up to TDC, resulting in a scrap engine.

I suffered the plastic flap failure on my Saab at pretty much the worst possible moment - February, at night, blizzard conditions, me, wife, teenage son and both elderly parents in the car and all on the way to East Midlands Airport to catch a plane to Tenerife to celebrate my Dad's 80th birthday - when the engine went into limp-home mode with twenty miles still to go.

The car wouldn't pull more than 15mph and a friendly trucker tailgated me all the way to the airport almost touching the back of my car and repeatedly blowing his klaxons. I guess he thought I was just driving like Miss Daisy because of the blizzard and should have gone faster, but I couldn't, I daren't stop in case the engine died and he couldn't overtake because of the heavy snow which was rather ironically swirling around us.

Apparently removing these flaps doesn't noticeably affect the idle, while engine performance and MPG are both significantly improved, especially if the EGR is blanked off at the same time.

Thanks for reminding me about this issue, it's made me realise that it's time I sorted it on my new future classic Alfa.

[zagmad]

Not heard from lusso yet so ive got my car booked into to have new flaps put in as my car has done 75000 miles so sounds like it could do some fresh ones, till I find an engineer who can sort the deletion process. And egr .

[zagmad]

I don't think I mind so much if their was a kit made from metal for the posts that go in as their the things that seem to droop and eventually effect the flap angle and drag ,as well as the soot build up. Or just make the flaps narrower . Plastic parts who'da thought in a hot engine.