Ill Engine: juddery

[Bowlerwell]

Hi folks. Maybe you can help me...

This has happened on and off over the past few weeks, but was quite bad this morning.

At idle, i can feel the car shaking/juddering... not smooth as usual.
It sounds wrong from the outside... kinda rough...
Awful smell present. (Sulphur Dioxide?)

I noticed today that my temp. was over 90... it usually rests jusat under 90. This may or may not be related, I had been motorway driving, then come intot he city.

Any ideas what could be wrong? Fuel Mixture?

Hope you can help,
Thanks,

JohnB

[s2driveruk]

are you sure its firing on all 5 pots? was the fan kicking in and out? these cars tend to have slightly lumpy idle but nothing severe, could be something as simple as a hole in a vaccum line or something far more serious

[Bowlerwell]

No, I'm not sure if it's firing on all pots...
Not sure about the fan either... but my temp did drop when I got up to 40Mph.

No, this idle is far worse than usual.

Where's my Vacuum line? What does it attach to, and what does it do?

Thanks!

JB

[Graham]

I have seen a clogged exhaust (Usually caused by degraded CATS) cause this and stall the car completely. Check the timing belt aswell if it jumps a tooth it will cause it to judder, but if it jumps a few more teeth its valve clobbering time and £££££££££££££££££££££££££ ££££££
To see if its mis-firing, with the engine ticking over, unplug and re plug each injector plug, if you can unplug one and it makes no difference to the lumpy tickover, then there is a problem with that cylinder.
HTH
Graham

[s2driveruk]

there about 400 miles of vaccum line in the S2 is it a 3b? if so coule maybe be just one of the HT leads, check their condition? There are lines from the back of the IM if i remember but they run off in all directions, can you hear any leaking air under boost or at idle?

Sorry I can't help more, sure someone more tech minded will come along soon!!!

[Bowlerwell]

Thanks folks!!

No, it's ABY.

I don't think I get leaking air, but I do get a strange whirring noise when I rev over ~3k...

[Bowlerwell]

ok, So i went to http://www.s2-audi.co.uk/tech_articles/spark_plugs.htm and discovered how to get into the spark plugs... then re-read the thread and realised you said injector plugs... oops.
Are they easy enough to come out?
I need to undo the clips first, right... then I can safely unplug 1 cylinder at a time without causing damage?

If anyone else has any more ideas or suggestions, please let me know.
Thanks,

John

[Graham]

With the car ticking over it wont cause any damage over a short period, to unplug an injector simply grip the electrical plug on the injector with your thumb on the little metal bar which goes around it, squeeze in the bar till it touches the plastic and pull, the plug should come off easily. Mine is a ABY same as yours (Same colour aswell-Kingfisher). It wont do any damage as although it will not be firing on the cylinder you unplug, it wont be injecting fuel either, so no damage to the CATS.
HTH
Graham

[Graham]

The plugs are tight but here is a little how to:

[Bowlerwell]

Thanks Graham!!

Wow, it's been a long time since I got such a comprehensive answer.
Pictures too!!

Thanks!

JohnB

[Graham]