Intake Manifiold To Sad Tube Question

[soundguy 13]

My 205 just scraped through the emissions due to a high and rich idle. What I've realised is that all three AFMs I've acquired over recent months are xxx 056s. Until I get a xxx 109 unit, what are the implications of slightly choking the pipe from the bottom of the inlet manifold which goes (apparently?) to the SAD?

 

The only way I could get the idle speed down during pre MOT tinkering (ie, over the last four days) was to switch on all electricals and restrict this pipe - the screw on top of the throttle body is in tight, and the screw under the tamper proof cover won't budge.

 

So until I get the right AFM, if I run the car with this pipe chocked, will it cause damage?

[welshpug 1,657]

sounds like the throttle stop screw needs adjusting, or the throttle switch, as you should be able to get the idle speed down near the 1k rpm mark at least with the idle screw even with the SAD wide open

[Anthony 1,003]

Choking the SAD pipe won't cause any damage, but there's another underlying issue rather than just the AFM being incorrect causing the high idle speed.

[soundguy 13]

Yep, the throttle stop screw needs to be freed up one way or the other, so going partially remove the throttle body, turn it over to see if there's enough protruding screw to get the molegrips on tight, see if that will back it off a bit - plusgas next.

 

I've checked for leaks at all connections I can, tightened all the clips up and replaced a few just to make sure. Going to look at the tachymeter relay as well, see if it needs corroded etc. Made up a silicon gasket for the air cleaner/air filter box which now seals up nicely.

 

Was wondering if the distributor affects the mixture, any thoughts on that?

[smithy 1]

sounds like you have a few issues to me.

 

to bring rpm down by choking SAD pipe sounds like either sad is wide open,pipe is split causing air leak or the body of sad is loose causing an air leak. My sad was loose causing it to suck in air i covered it in silicone sealer around joint on body as temp measure until i got a replacement.

 

Have you removed the clip that holds the throttle stop screw in the body tight? follow the set up procedure for throttle flap and TPS checking/adjusting in haynes,personally i find it easier to remove throttle body to do this.

 

Might also be worth changing the coolant temp sensor.

[soundguy 13]

Thanks for that smithy, I'll have a proper look at the SAD and pipework for splits etc. The throttle stop screw didn't have a clip, just a tamper proof plug. Prized that out but the screw underneath is seized (supposed to be a hex key bolt?). Anyway, tried to get the throttle body off today but lack of appropriate tools meant I was at risk of rounding some heads off, so I'll need to pick a few decent spanners up first.

 

Will definitely look at the process in the haynes re: TPS/flap, and coolant temp sensor. Ta.

[dave richards 26 1 Cars]

Thanks for that smithy, I'll have a proper look at the SAD and pipework for splits etc. The throttle stop screw didn't have a clip, just a tamper proof plug. Prized that out but the screw underneath is seized (supposed to be a hex key bolt?). Anyway, tried to get the throttle body off today but lack of appropriate tools meant I was at risk of rounding some heads off, so I'll need to pick a few decent spanners up first.

 

Will definitely look at the process in the haynes re: TPS/flap, and coolant temp sensor. Ta.

 

 

sounds to me like you looking at the afm not at the throttle body

[martin81 1]

Edit: nevermind

Edited July 28, 2011 by martin81

[smithy 1]

My throttle stop is a small flat head and has never had tamper proof cap. Mine is xu9 with jetronic injection

What engine and injection is yours as it sounds like it has different throttle body to mine.

[soundguy 13]

sounds to me like you looking at the afm not at the throttle body

 

Definitely the throttle body, immediately to the right of the intake manifold.

 

To the left of the throttle cable spring mechanism - it's a small screw, flathead, under a 5mm diameter black plastic cap. I can feel it protrude and the 'throttle stop' is against it at rest/idle. If I can back it off, the idle speed should drop.

[soundguy 13]

My throttle stop is a small flat head and has never had tamper proof cap. Mine is xu9 with jetronic injection

What engine and injection is yours as it sounds like it has different throttle body to mine.

 

D6B, yellow injectors fed by a rail (so LE2?), 1.9 ECU (ends with xxx 359), but running a 1.6 AFM (xxx 056). I'm just looking at the haynes manual, section 4C*3, illustration 10.7 - same throttle body. Just to recap, the air screw is right in and the throttle stop screw is seized.

 

Incidentally, the throttle stop screw is recessed into the TB by about 6-7mm - it's not flush with the surface or anything.

Edited July 29, 2011 by soundguy

[welshpug 1,657]

D6B, yellow injectors fed by a rail (so LE2?), 1.9 ECU (ends with xxx 359), but running a 1.6 AFM (xxx 056). I'm just looking at the haynes manual, section 4C*3, illustration 10.7 - same throttle body. Just to recap, the air screw is right in and the throttle stop screw is seized.

 

Incidentally, the throttle stop screw is recessed into the TB by about 6-7mm - it's not flush with the surface or anything.

 

all the throttle bodies I remember seeing the screw protruded out by a a good few mm when set correctly, so it may well be that youve found part of the problem.

[smithy 1]

As welshpug said stop screw protrudes out about 5mm on mine.

 

Sounds like you definitely need to have body off to clean out and set up properly,could have had a different screw fitted at some point in it's life that's why it is not same as normal?

[soundguy 13]

Bit of relevatory afternoon with the spanners - was noodling around a bit under the bonnet then cast my eye over the old seized engine in the boot (1.6'er) ...and realised it had not just a complete throttle body still attached, not just an SAD unit, but also a small handful of sensors still attached, as well as the inlet manifold and injectors, rail etc.

 

So I've whipped the old SAD off and it is open like you suggested, smithy. The replacement one has a gap at least half the size showing when I look through it, so that's got to be an improvement.

 

Going back to the replacement throttle body, the air screw is easily adjustable, as is the throttle stop screw - which has the clip going across it rather than a recessed flat head screw. Once the SAD's back on I'll swap the TB after a good clean, then I'll be on the lookout for a good 1.9 AFM.

 

So not only have I got some good parts all ready to replace the problem ones, I've got a few extra bits I can sell off as well - now that's what I call a happy Friday!

[smithy 1]

should be all good once TB set up and 1.9 AFM fitted.

 

with the SAD i tested mine by blocking hole on one side and sucking on the other i could clearly hear and feel a leak around body,also do the test in haynes where you put 12v on connector and after 5 mins should completely close up.

[soundguy 13]

should be all good once TB set up and 1.9 AFM fitted.

 

with the SAD i tested mine by blocking hole on one side and sucking on the other i could clearly hear and feel a leak around body,also do the test in haynes where you put 12v on connector and after 5 mins should completely close up.

 

Okay I'll check for leaks after I've put this new tin of degreaser to work. About the haynes test, the only reference I can see to the SAD is section 4C*4 - gives the removal procedure but nowt re: testing. Doesn't matter though, found this after searching with the phrases from your post, so thanks for the suggestion:

 

http://forum.205gtidrivers.com/index.php?showtopic=106532&st=0 - '12v to SAD unit'.