Audi A3 + S3 (1996 - 2001) - 1997 1.6 - Car juddering while accelerating.

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Mon 6 Oct 2008 16:43
1997 1.6 - Car juddering while accelerating. - Banksie
Hi all,

My 1997 Audi A3 1.6 developed a problem yesterday while driving on the motorway in heavy rain (don't know if that's relevant). Basically, in all gears from 1000 to 2500/3000 revs it judders while accelerating, after which it runs smoothly despite an obvious lack of power - I can get to 80mph in 4th gear but 5th gear does practically nothing, whereas before 4th gear would be at quite high revs and 5th would accelerate the car still.

What could this be and how much will it cost to fix?

Edited by Pugugly on 06/10/2008 at 21:37

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Mon 6 Oct 2008 16:59
1997 1585 Car Juddering while Accelerating. - Screwloose

Plug; plug-lead; coilpack? When were those almost inaccessible plugs last changed?

Have a look at the engine when it's totally dark and idling; maybe spray a little water on the leads and see if you can see - or hear - anything.
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Mon 6 Oct 2008 17:18
1997 1585 Car Juddering while Accelerating. - Banksie
I only bought the car in July so I have no idea when they were last changed. I'll try to have a look at it tonight, then, if I can get the engine covers off! Thanks.
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Mon 6 Oct 2008 21:21
1997 1585 Car Juddering while Accelerating. - Banksie
Update: I had a look and no sparks at all. I did remove the HT leads from the ignition coil and one of them was completely clogged with a powderey white residue which I tried to scrape out with very little success. I'm guessing I've found my problem but what do I do? Could I just clean it out with water?
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Mon 6 Oct 2008 21:37
1997 1585 Car Juddering while Accelerating. - Screwloose

Boiling water sometimes dissolves that stuff; but if it's salt-based metallic corrosion, maybe only a specialist electrical contact cleaner will work.

A new coilpack and set of leads would be the normal solution in a workshop.
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Tue 7 Oct 2008 10:23
1997 1585 Car Juddering while Accelerating. - Banksie
WD40 seemed to clean it all out but the car still has the same problem.

The coilpack (I've called it "ignition coil" above) it's definitely this thing, right?

img00.madeinchina.com/products/058/582/1058582.mic...g

It's the bottom right "tube" where the ignition leads plug in that has all the corrosion in.

Edited by Banksie on 07/10/2008 at 10:26

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Tue 7 Oct 2008 12:53
1997 1585 Car Juddering while Accelerating. - Peter D
You are starting to throw money at the problem. Find a local Audi/Vag indi and get the codes read. I would not be surprised if the Air Mass Meter fas failed. Regards Peter
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Tue 7 Oct 2008 14:19
1997 1585 Car Juddering while Accelerating. - Screwloose
Banksie

Yes; that's the coilpack.

Whether the high resistance in that plug has damaged it - or the lead - is now the question. Is there a spark on that plug?
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Tue 7 Oct 2008 16:07
1997 1585 Car Juddering while Accelerating. - Banksie
No spark, no but that's probably because there's no connection from the coilpack to the plug. I reckon it's a dodgy lead (it's a shorter, different lead to the others which look A LOT newer) but I've ordered a new coilpack off t'internet and will install it tomorrow. Hopefully that'll fix the problem in the short-term and on payday I can replace all the leads.
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