Sad Issues

[gti_al 1]

Today (aside from removing the bloody gearbox again) i put a different SAD in to try and sort my cold start problems... Since the new engine has been in it constantly idles at 2k+, and even with (what i was told) was a good SAD it hasn't changed.

 

I'm starting to think something else must be responsible, as the old SAD worked ok on the old engine, and the new one apparently worked as well... I have done a search to try and highlight any other problems, but most seem to just be attributed to a dodgy valve.

 

Could it be something else?

[Revla 2]

Today (aside from removing the bloody gearbox again) i put a different SAD in to try and sort my cold start problems... Since the new engine has been in it constantly idles at 2k+, and even with (what i was told) was a good SAD it hasn't changed.

 

I'm starting to think something else must be responsible, as the old SAD worked ok on the old engine, and the new one apparently worked as well... I have done a search to try and highlight any other problems, but most seem to just be attributed to a dodgy valve.

 

Could it be something else?

 

Could be the air flow meter? Have you had the mixture reading recently?

[petert 586]

Could it be something else?

 

 

you know what to do Al...............

[gti_al 1]

you know what to do Al...............

 

Are you getting at what i think you are...? I actually noticed that my cam seal is leaking a bit today, but after spending (yet) another day on that engine i would like it to stay.

 

I did speak briefly to the person who has been helping me about doing a head swap though, so you may be hearing from me about prepping a head.

 

And i believe the AFM is good. I leant it to someone who compared it to theirs, and they said that their car ran far better on it. The car is also running perfectly without a SAD, but i suspect when it cools down it may become more challenging...

[jonD6B 0]

Could be a vacuum leak? Does the idle slow down if you kink the SAD breather pipe?

[Guest yaztromo]

Bad throttle position sensor?

[simonb 0]

TPS will not cause a high idle. It WILL be any of the following:

 

1. AFM - spring far too loose causing the flap to open too much. Has this been messed with recently?

 

2. Idle screw too far out. Wind it in to reduce the revs.

 

3. SAD stuck open. Squeeze the pipe leading to the sad from the intake. If it goes down will be this.

 

4. Split pipe from SAD to inlet manifold. This happened on mine a while ago when the hose split where it joins the underside of the inlet manifold.

 

5. Throttle butterfly getting stuck. Check the throttle cable allows the butterfly to close fully and that its operation is smooth when rekeasing the throttle. Also check the throttle stop screw as this might be too far in.

 

6. Air Leaks in inlet manifold / oil filler housing bolt that attatches to the manifold.

 

These are the only places that will cause high idles, so it's bound to be one of them. Pay particular attention to the piping going from the SAD to the inlet manifold as it can be tricky to check without removing the radiator.

 

HTH

[gti_al 1]

Thanks heaps for that Simon, it is exactly what i was after...

 

I'm fairly sure it has something to do with the sad, but it seems unlikely that my old SAD died in the six months the car was apart, and more unlikely that its replacement died in the mail from England... This does indicate a leak in one of the hoses or maybe an issue with the idle screw. (although the revs would still drop once it warmed up, wouldn't they?)

 

I know that it is SAD related as i have been running the car for a while with one of the hoses permanantly kinked. (I know it is dodgy, but when it is warm it doesn't need help to start.)

[pug_ham 244 3 Cars]

Could be the same problem as in the topic I posted about last week on here about Fidod's car, the SAD isn't closing. (which we've yet to cure ).

 

I can't see an SAD getting damaged in the post causing it not to work, more likely a wiring problem. That would take some serious amount of doing.

 

I agree that I wouldn't think the idle screw would be causing this to happen & if as you've proved that blocking the SAD stops it idling high.

 

Check the voltage at the SAD plug & let me know what you have there, both across the plug terminals & from input direct to battery earth please al.

 

Graham.

[gti_al 1]

It does sound very similar graham. I have been following that topic, although i had forgotten about it when i started this thread. Sorry about that.

 

I have been thinking that it must be a wiring problem, although that is one area which i am extremely clueless in... I will try and get those figures for you though, as i want to get to the bottom of this.

 

Also, i think i have eliminated the hoses as they all look good. It also wouldn't make sense if something near the inlet was leaking, as when you kink it at the T/B end it idles perfectly. (when warm) Surely if there was a leak at that end it would still idle high, even when the hose is kinked?

[Guest JonRP]

Just an idea, but have you made sure the SAD is the right way round? In my learn by mistakes way of doing things, I had the air flowing the wrong way and the valve, although closed, does not seal and caused an idle of about 2k. Replaced every hose and the AFM before working that one out

 

Jon

[gti_al 1]

Just an idea, but have you made sure the SAD is the right way round? In my learn by mistakes way of doing things, I had the air flowing the wrong way and the valve, although closed, does not seal and caused an idle of about 2k. Replaced every hose and the AFM before working that one out

 

Jon

 

That sounds like the kind of mistake i would make... I take it the wiring plug on the sad should be facing the firewall?

[pug_ham 244 3 Cars]

I wouldn't think it can be fitted the wrong way round causing this problem.

 

Its basically a simple tube with a disc that blocks the hole up after a short while & fitting the pipes on the other sides wouldn't make the slightest bit of difference imo.

 

Yes if you have fitted it the opposite way round the plug will be facing the bulkhead (firewall).

 

Graham.

[gti_al 1]

So i have fitted it the wrong way around? Here is the pic from the guide on website - i have it with number 1 pointing to the front of the car, and 2 the back. It really shouldn't make any difference though...

[gti_al 1]

Just an idea, but have you made sure the SAD is the right way round? In my learn by mistakes way of doing things, I had the air flowing the wrong way and the valve, although closed, does not seal and caused an idle of about 2k. Replaced every hose and the AFM before working that one out

 

Jon

 

Not having a SAD has been driving me crazy, so i pulled it out today... After being dropped in hot water it seemed to be closing perfectly, but after refitting it (the right way around this time ) the thing is still idling high.

 

The idle screw is in fully, and the idle is still around 1250 - 1400. Could this indicate an issue with the way the AFM is set up? Is there a default setting or something for it?

[richsmells 2]

sounds like an air leak. as already mentioned, manifold gasket, oil filler bolt etc. Spray some WD40 around the the inlet manifold area, if you hear the revs dip then you have a leak somewhere.

[gti_al 1]

It does look like an air leak, but all is solved by kinking the SAD hose. (this would rule out a leak between the SAD and inlet, plus a leaking gasket wouldn't it?) That isolates the valve itself , but it closed really quickly in hot water.

 

It is definately behaving much better now that i've turned it around and cleaned it out, but the only other potential problem is the wiring. I haven't checked this, (don't have a multimeter) but it was fine before the engine was swapped.

 

What does the wire to it do anyway? I thought the thing just closed when it got hot... Does it get a signal from the water temp sensor or something as well?

[gti_al 1]

Also, when the car is hot and the sad is kinked it idles at 1000rpm. (with the idle screw completely in) That seems like a lot...

[gti_al 1]

What does the wire to it do anyway? I thought the thing just closed when it got hot... Does it get a signal from the water temp sensor or something as well?

 

Anyone? Could it be that my water temp sensor or something isn't working, so it is not telling the SAD to close or something?

 

Does it even work like that? I'm getting tempted to drop an Mi16 in just to fix this!

[richsmells 2]

No, I think a voltage is applied to it when the car starts warming up and this heats a bi-metallic strip, closing the valve.

[futura 3]

The way you tested the SAD valve sounded odd to me

 

The right testing procedure consists in taking it off the car, and applying 12V to the pins (red connector is 12V, blue one is GND). It should close completely after 5 minutes.

Edited July 30, 2006 by futura

[gti_al 1]

Thanks mate. I read here the easiest way to test it was warm it up in water, but your method sounds better. I might drop my spare valve off to an auto-elec and get him to check it. It is driving me crazy not being able to just jump in and start it...

[gti_al 1]

I had another go at fixing this today, and my spare SAD isn't working either. The other one had actually started idling at 1000rpm by the time i got to uni, (an hour away) but it wouldn't make the revs rise when the car was started. Generally it would take a minute or two for the revs to rise up to 1500, then about 45 minutes for them to drop down to 1000.

 

I put the spare valve in, and the revs don't rise now either. I haven't started another 205gti from cold, but surely you don't need to use the accelerator to start them... This problem couldn't be attributed to dodgy wiring either could it?

 

Should i try to get another SAD that can definately works? This prob couldn't be caused by anything else, could it?

[ALEX 98 1 Cars]

The way you tested the SAD valve sounded odd to me

 

The right testing procedure consists in taking it off the car, and applying 12V to the pins (red connector is 12V, blue one is GND). It should close completely after 5 minutes.

 

Do this test to each of your SAD's.

This method eliminates the SAD as the problem.

 

Thanks mate. I read here the easiest way to test it was warm it up in water, but your method sounds better.

 

Sounds like your thinking of the thermostat here!

[gti_al 1]

Do this test to each of your SAD's.

This method eliminates the SAD as the problem.

Sounds like your thinking of the thermostat here!

 

I will get them both to the auto elec tomorrow... I would do it myself but i don't really have the equipment. And i don't know where i pulled that testing method from - i just did a search and the first thread suggested it.