SAD issues

[Richie-Van-GTi 74 2 Cars]

How well does the SAD close off? Mine still passes a lot of air but the plate looks closed inside when hot. Literally can wind the throttle bypass full closed and throttle stop fully back and it idles at 1100. Pulled the pipe off the sad and there is a stack of air going through it.

[Tom Fenton 1,562]

It should shut so it passes next to nothing. Clamp the hose going to or from it and see what the idle speed does. When working properly and you clamp the hose, there should be no change in the engine speed (assuming fully warm). 

[Leslie green 126]

I noticed mine was the same  throttle screw fully closed and butterfly closed and still 1100 rpm , will need to check once I get mot over. 

[Thijs_Rallye 89 4 Cars]

If there is no change to the idle RPM after clamping the hose as Tom suggested, check for air leaks at injectors / seal surface of intake manifold and most importantly all oil breather and fillers hoses.

[Richie-Van-GTi 74 2 Cars]

On 4/4/2025 at 8:49 AM, Tom Fenton said:

It should shut so it passes next to nothing. Clamp the hose going to or from it and see what the idle speed does. When working properly and you clamp the hose, there should be no change in the engine speed (assuming fully warm). 

Half hour of heater on and heated the housing to scalding and I can still blow through it easily, no split pipes etc. it is reduced from fully open but certainly not a struggle by any means. Tried adjusting it both ways and no difference, knackered???

6 hours ago, Thijs_Rallye said:

If there is no change to the idle RPM after clamping the hose as Tom suggested, check for air leaks at injectors / seal surface of intake manifold and most importantly all oil breather and fillers hoses.

No difference when blocking hoses either but can't find any splits etc, seems like the oil breather just passes through the cap and gauze to the elbow on the other side if the throttle body though, normal??

[Thijs_Rallye 89 4 Cars]

There is a breather hose that runs from the top of the valve cover to the T at the bottom of the oil filler hose, oil filler hose should also be free of splits and are often hard to see without removing them imo. Then there is a breather hose that runs from the bottom of the engine block to the side of the oil filler "pot" or however it is called. Another item often overlooked is the bolt that bolts the oil filler pot to the intake manifold. A pin hole is enough to throw off your idle so look closely.

[Richie-Van-GTi 74 2 Cars]

16 hours ago, Thijs_Rallye said:

There is a breather hose that runs from the top of the valve cover to the T at the bottom of the oil filler hose, oil filler hose should also be free of splits and are often hard to see without removing them imo. Then there is a breather hose that runs from the bottom of the engine block to the side of the oil filler "pot" or however it is called. Another item often overlooked is the bolt that bolts the oil filler pot to the intake manifold. A pin hole is enough to throw off your idle so look closely.

All hoses etc are fine, there is no air leaks, the issue is the SAD lets a lot of air through when closed.

[Telf 232 2 Cars]

Buy a new one! They don't really let anything through when closed.

[bacardincoke 43 1 Cars]

Was going to start a topic of my own, however this recent one leapt out at me and has some elements in common / save repetition.

 

1989 1.9 - has run perfectly for a number of years, though mileage is minimal these days (about 300 in the past 2 x years).

 

Serviced regardless / turned over regularly etc.

 

Getting it ready for this year and noticed the cold idle now rises to around 1900 rpm (previously it'd be a max of 1450 rpm).

 

It'll remain there for several minutes, then progressively drop down over course of about 5 minutes to a rock steady 950 rpm.

 

Squeezing the inlet / outlet pipes (while still warming up) to the SAD will cause the revs to drop to point of almost stalling.

 

SAD out today.

 

The open 'pie slice' is there at cold (size / shape matches what others seem have on working SADs).

 

12v through the element on it's own will cause the opening to close, but it can be in excess of 10 minutes (it's the very last tiny glimmer of a hole takes forever to finally shut).

 

Supplement the 12v with heat from a gun and not surprisingly it'll close in much quicker, but hard to quantify as the combination is hard to keep consistent.

 

The last little bit also closes much more quickly when 12v + heat gun.

 

Washed through the SAD with brake cleaner / small amount of plusgas afterwards to re-lubricate the moving window and it's made a difference, though nothing dramatic.

 

At the moment I'm going to tentatively assume the SAD is working correctly, what's stopping me being more confident is I've SAD's from MK1 Golfs on Kjet (called something else in VW circles) and they are confirmed working.

 

They take 2 mins 30 secs to close on 12v only (and consistently).

 

I understand they're completely different things, and there may well be such a wide variation between them, can someone confirm 10 plus minutes for the 205 one is to be expected?

 

When I was looking into this, I notice the pipe from the SAD outlet to the underside of the intake manifold gets 'sucked in' (for about 10cm of its length at the manifold end near the built in kink and not else where), when cold starting... it's like theres a vacuum?

 

It was a new BBM one (4 years old now)

 

Tun the car off and the pipe flexes back out to it's normal shape... when it's 'sucked in' it doesn't appear to influence any thing, air can still pass though presumably at a reduced rate. If I squeeze the 'sucked in' pipe while cold starting the revs will drop to near stalling.

 

If it weren't for the fact the car now out of the blue idles to 1900rpm before dropping to a warm idle, when before it was 1450rpm nothing has changed... runs like a dream as it always has.

 

Did the CO a few days ago and its 1.6.

 

I haven't put the SAD back in yet (issue may be resolved, hopefully) but it's a pig of a job and I didn't want to do it, to then be told there was something else I could have done while it was out!

 

Bit of a ramble, apologies...

 

 

 

 

 

 

 

 

 

 

 

 

[Leslie green 126]

On 4/9/2025 at 1:36 PM, Telf said:

Buy a new one! They don't really let anything through when closed.

Remaufactured sad valve is 360 with a well known supplier which seems a bit pricey,  same as an afm refurb !. I have found you can buy a kit to repair the quadrant but it won't fix a faulty heater .

[bacardincoke 43 1 Cars]

Cheers... found this just now, so if correct further supports the SAD seems to be working.

 

Don't want to go off at a tangent, one for another time, but it had crossed my mind before if it would be possible to make up a 205 SAD from say a MK1 Golf one (or vice versa / or any other), using one of those kits plus the still working bits from which ever?

 

 

 

 

 

 

 

 

 

Edited Tuesday at 10:06 PM by bacardincoke

[bacardincoke 43 1 Cars]

Meant to say the SAD is Bosch  0 280 140 182 (Peugeot equivalent 0345.37) for the 128hp 1.9 1987 onwards, so correct to the car / engine.

 

It's date marked October 1998, so not all that old (car's done small miles from then to now).

 

 

[Leslie green 126]

Seems yours is OK electrically and just not closing fully , maybe a new disc and spring will sort it , it's worth a go at 35 quid . There are 3 part numbers can't see there being much difference as one repair kit fits all 3.im not sure what actually goes wrong inside yet maybe it gets gummed up and jams .

Edited Tuesday at 10:27 PM by Leslie green

[bacardincoke 43 1 Cars]

Bit of an update... just finished buttoning up everything and theirs possibly some small improvement, but it's not that there was anything you'd call a problem before, just slightly different behaviour than remembered / expected.

 

Satisfied the SAD is working as it should, have found some Bosch data and the Ohms across the terminals of 0 280 140 082 should be 49 (that ties in with the Autodata range of between 45-55 quoted by Mossy).

 

Air volume is 10 m cubed/hour at 20 degrees.

 

This two things appear to be what differentiates one SAD from another - the resistance of the heating element (time it takes to heat up) and the shape / size of the aperture of the disc as it rotates (flow rate).

 

I've had a quick look at some others used in various different marques and while there's some that are 49 Ohms and some that are 10 m cubed/hour, so far I haven't found one that exactly matches both (I suppose if they did, they'd just use 182 and not another!), though a few are very close and in the real world could maybe work with no descernible difference to running.

 

As Leslie says there a kit available to refurbish these, but it doesn't include the heating element.

 

From what I understand if your SAD has died altogether it's likely it's the culprit.

 

The bi-metal element has a finite life and eventually just stops working.

 

Other causes can be a build up of (carbon?) within the unit that prevents the disc / window either moving at all or in a limited way.

 

That can be successfully sorted with a clean out.

 

I've also seen references to the spring coming adrift, though that's more to do with the hole it secures to the plastic disc by wearing through, maybe those kits are aimed at that scenario?

 

 

 

 

 

 

 

 

[Leslie green 126]

That's interesting I have bought the kit so as soon as I can test mine and see if its passing I will try and take it apart , I thought the kit was worth a punt given how much a repaired one is . I thought mine was working when it first got back on the road a couple of weeks ago as it brought the revs up to 1500 straight away then dropped back but now all sorts of silly things are happening like one time a misfire on startup( I read of a similar case on here linked to a sad issue) that if I held a rev cleared and other times it revs then hangs then revs then near cuts of a couple of times until you hold a rev on and its also revving to high when warm at 1200-1300 rpm.

I saw autodoc had ones at like £140 new but out of stock at the minute and possibly a long time I dunno.

I wonder whats been fixed on the refurbed ones as maybe the heating element can't be changed so they may not be very long lasing , really you need new 

Edited Thursday at 03:13 PM by Leslie green

[bacardincoke 43 1 Cars]

I'd a quick tinker with the cold / hot idle post cleaning the SAD, and plan to properly set it up again along with the emissions, even though it was done a week or so go.

 

Cold start is now down to about 1600rpm, with hot idle remaining at the previous 950rpm, so it's had some influence and worth doing.

 

I could tweak the cold idle down further to around 1500rpm, but that starts to have a knock on effect on the warm and while 850rpm is probably acceptable, my personal preference is a little higher and what I'm used to, plus to my ear the engine just sounds happier too.

 

It's the sucking in of the SAD return pipe to the manifold that's puzzling me, its clearly the inlet vacuum doing it, briefly rev. things and it'll expand out, before contacting again on idle.

 

It may have always done that and I was unaware as it's out of sight... just seems bizarre.

 

Bosch do still make a surprising amount of K-jetronic parts for MK1 Golfs, and that's where my main interest lies, it just so happens this style of SAD (I keep wanting to type Auxiliary Air Valve!) is also part the Peugeots set up.

 

Unfortunately I'm not aware of them making/remaking these (yet), if you know differently let us know.

 

I touched on it above - electric elements of 49 Ohms are in a number of non-Peugoet SADs, if the relevant 205 disc / apperture (from a kit or bust 182) could be transferred to one of these you'd be able to create your own to exact spec.

 

The fly in the ointment is most SADs, regardless of what vehicle the originated in, now seem to command big money, plus factoring in £35+ for a refurb kit (if you don't have a  broken 205 donor) makes for quite a bit of money, maybe even more than getting a working original... but then that's the rub, they're not exactly thick on the ground.

 

 

 

 

 

 

 

[bacardincoke 43 1 Cars]

@Leslie green

 

Had a look at the refurb. kits (mainly on eBay), and guessing it's the 'Missingparts' seller from Germany you got from?

 

Which version did you go for?

 

Interesting that they're lumping in so many different SADs together for each of the 3x versions.

 

The Bosch stats. show there's quite a variance of flow rates for those in each of the groups, so have to assume they must deem the differences negligible (eg. 7.5 m cubed / hour over 10 m cubed / hour) and it's probably more down to the differences of the aperture profile (hence their three types).

 

If you're minded to do it, could you stick up some images of the kit and maybe even of your refurb at various stages etc?

 

 

 

 

 

 

 

[Leslie green 126]

Yes that's the seller , I'm thinking they just have one version , it probably not that important how much it flows but more important  rather it opens when cold and closes when warm (eBay item number:185447920935) . I will stick some pic up yes , I hope to test the heater next week and see if its even worth repairing but even if its not I may take it apart just for a look and block it off completely till I get another . The sad is maybe only one of my issues but until its sorted it makes it hard to find the real issues . Currently it warm idles at 1300 rpm and cold can be every erratic too but when warm the car is lightly shunting at speed under load , that isn't sad related and could be any of a number of things from timing to fuel pressure, too much engine movement , dissy vacuum advance busted or the vac line to it who knows , its been offroad 19 years and was running fairly well for the first few runs but now its like  a bag of spanners .

Edited Friday at 04:10 PM by Leslie green

[bacardincoke 43 1 Cars]

Great, thanks... keen to see how it actually comes apart after you drill out the 4x pegs on the rear.

 

Have seen some Alfa forum posts where they've also ground away the circumference (likely wrecking the thing), but I think that's maybe them not really knowing what they were at!

 

Some others I found seem to show heat needs to be applied and the halves prised apart... might be something in that, you seem to get some epoxy with your kit, perhaps to reseal it?

 

I've a few SADs from other cars here, one's from a B2 Audi 80, specifically the 1600cc GTE.

 

Bosch say it's 49 Ohms + 9.5 m cubed / hour, but what particularly caught my eye was the aperture is visually identical to the 'pie slice' of the Peugeots (size, position etc.) so have looked into that one a bit further saying as they're such an all round close match.

 

Turns out the same SAD that Audi 80 used was also in multiple other cars one of which was the D2A (XU92C) 1987 - 89 205 1.9 (102HP).

 

Not sure any of that's much use, trying to find one of those is probably as difficult as it would be the correct one anyway.

 

Does show though, that when you dig down into the numbers / specs. there's potential for alternatives to be found.

 

 

 

 

[Leslie green 126]

When out a run to my garage ( 40 miles) in the 205 , I put so millars ethanol additive I just got in the fuel and it isn't as bad as the last day but the fault is still there .I  looked at an old 1.6 engine I had in the corner  and it still had the sad on it , happy days.

I've ohmed the heater and its 46 ohms , I was going to connect it to a battery but the pins are very close and not sure which is + but neither pin is grounded to the case so may not matter , do you know which side is plus ?

The instructions said drill a 3 mm hole 3mm deep but I suspect it's a bit more tricky than that , those 4 pegs are pressed into the other side and that and I'm guessing some sealer holds it together ,once they are gone there is nothing holding it anymore I can see through the little opening when cold so that's a start just want to find out if it will close when the heater is on .That 2 pin isn't the same size as the ecu temp sensor by the look of it its smaller as i have one of those plugs new.

 

 

Edited Friday at 08:43 PM by Leslie green

[Leslie green 126]

Little bit here in this thread on testing : This sad I have now is a different part number 0280140112 of a 1.6 205 gti from the 80's

 

 

 

Edited Friday at 09:39 PM by Leslie green

[bacardincoke 43 1 Cars]

0 280 140 112 is the Audi 80 one I was talking about above, which closely matches the spec. of 0 280 140 182.

 

112 is listed for some 205 1.9 GTI's (plus a few 309 / 405 1.9's along with other manufacturers) but they are lesser powered versions (102HP), so perhaps vehicles for non UK markets?

 

Check your spare engine code and it may clarify things further, alternately someone else in the past may have by luck or design realised 112 potentially works, just guessing.

 

I'm not familiar with 1.6 GTI's, but I think i'm right in saying 182 is the SAD for both it and the UK 1.9, but check.

 

If so 112 wouldn't  be expected to have been originally fitted.

 

The 46 Ohmns of your 112 would be in spec. with the 49 given by Bosch for 182, if we use a range that spans in a similar way to the one quoted by Autodata.

 

If I'd twigged this before putting the 182 back into my car I'd have tested out the 112 first, just to experiment, you might be in luck and find it's a good alternative!

 

Said earlier that K-jet is more my thing, components for it that aren't on the L-jet of the 205 mirror what's going on with the SAD / Auxiliary Air Valve insofar as there's a mass of variations to suit a wide range of marques / engines etc.

 

One thing I have learned is K-jet is an amazing system, it is incredible how decades ago they mass produced the reliable / efficient / precision mechanical system it was.

 

 

 

 

 

 

 

 

 

 

Edited Saturday at 10:25 AM by bacardincoke

[bacardincoke 43 1 Cars]

Been looking back and forth through some Bosch data (it's in German, which I don't speak and am relying on Google, so subject to misinterpretation / error).

 

I've now found a few SADs that are all to 49 Ohms / 10 m cubed.

 

Unfortunately though it's looking like it's not going to be as simple as that, and this is going to echo what that particular eBay seller of the refurb. kits seems to imply... that there are 3x different profiles of apertures.

 

The openings on any of them don't appear to result in a linear flow ie. from the fully open position to the fully closed the air flow doesn't drop at an even rate.

 

Don't know if it's exactly like this, can't interpret the different shapes, but just for the sake of talk here and an imaginary example it may be that one profilelets more air through at the beginning of its cycle, then less as it closes, while another may do the reverse / or anything else in stages in between.

 

So Bosch seem to have mixed and matched resistance (heating element) / volume of air (size of aperture) and seperately the flow rate (aperture profile).

 

Doesn't rule out creating the desired SAD from the parts of others, just not as straightforward as first thought.

 

[Leslie green 126]

The seller has 3 separate ones when i looked further into it ,2 covers the one I thought my car would have the 182 (not checked yet) most of these changes are likely just updates and fine tuning if it lets air in at the start and closes fully when warm  it will do us .As for the one on my scrap engine its likely been swapped out with whatever they could find many years ago from a breaker  if it wasn't originally fitted .

The seller has sent me a email with the instructions in German  if you want it , looks like a heat gun is needed .You could certainly fit whatever shutter you want to change from one to the other as they are essentially the same housing and as long as the heater works it shouldn't really matter what exact size it is .

 

sad plug is same as injectors I should have a new one somewhere .

Edited Saturday at 02:26 PM by Leslie green

[bacardincoke 43 1 Cars]

Yeah, I think your seller gives buyers the option to pay for the specific one needed, hence having to choose between type 1 to 3.

 

There's another German seller who seems to be selling the similar refurb kits, but they include all three types, whether you need the other two or not, with a higher price to match.

 

Below is their image of the complete set of three,

 

When you open your (any?) SAD up one of these profiles will match the original.

 

Without going back to check, I did look at the kit you linked to earlier and from recollection it covered both 112 and 182.

 

Unless you have already unsuccessfully tried, I'd see if cleaning your 182 first makes a difference, before taking it apart.

 

These things are hard / big bucks to replace, a refurb. may ultimately not be needed, though worth the risk if only as a last resort.

 

I've always known those type of connectors as 'Bosch Junior Timers'.