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Old 26th June 2017, 01:07 PM
Resolutionary Resolutionary is offline
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Default Running issues on a newly bought D2

Hi all,

Regardless of the title thread I'm smitten with my recent purchase:



However, after buying I went on a 2 week holiday - my dad started it every couple of days to keep fluids moving and the battery in check.

Yesterday I took it on it's maiden voyage, did around 20 miles and parked up to do some shopping. When I returned to the car some hours later and started it, the engine check light was on. Later that day I ran a code scan and the following faults were found:

16814: Catalyst System Efficiency (Bank 2) Below Limit P0430
16804: Catalyst System Bank 1 Operation below threshold P0420

On top of this, when driving between around 1-2k rpm, I get an intermittent shudder which feels almost like a misfire pocket in the rev-range. There is also a bit of rev fluctuation during normal driving situations, in which I can visibly see the rev needle drop down 500 or so when I apply pressure to the throttle. I'm concerned it's transmission related but could equally be coilpacks / sparks.

I've driven it to work this morning and the engine check light hasn't reappeared (my friend reset the codes), although the noticeable issues persist. I'd really like some insight if anyone has experience of these issues, so I can rectify them as soon as possible rather than risk any further complications or lasting damage.

Thanks in advance folks!
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Old 26th June 2017, 01:55 PM
MikkiJayne MikkiJayne is offline
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The codes for the cats could be because they've not got properly hot. It doesn't really do the car any good at all to be started briefly but not driven as that introduces condensation in to the engine block and the exhaust but it doesn't get hot enough for it to evaporate so you end up with a lot of moisture where you really don't want it. It would be better for it to just sit there with a trickle charger on the battery and not to be run at all.

I would take it for a good blast and get the engine and exhaust properly hot (if its not going 'tink tink' when you stop you weren't trying hard enough!) and see how it behaves then.

The misfire could be many things but a common thing on the 2.8 is the cam cover gaskets leaking oil in to the spark plug holes. Worth pulling the coil packs and having a look to see if they're all clean. MAF can also do that although that does tend to manifest as a lumpy idle.

The rev fluctuation could be the torque converter, although 500rpm is a lot. Usually its only around 100rpm flutter. Does it bog down when this happens or pick up ok?
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Old 26th June 2017, 02:05 PM
Resolutionary Resolutionary is offline
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Thanks for the prompt reply MikkiJayne - I think you're right about the risk of condensation and as I have a free evening I will go for a spirited drive and see if any lights turn up during or afterwards. So far so good today on that front - perhaps just a blip? The exhaust does blow a little anyway so I am tempted by a stainless system, and will definitely do a thorough inspection while its on a ramp, whenever that may be.

The odd thing about the seeming misfire is it displays all the hallmarks for around half a second as you push on, then all signs of the issue disappear except for the fluttery revs. Perhaps 500 was an exaggeration but it's quite visible on the counter, and not something I noticed when I picked it up. That said, there is no particularly noticeable drop in performance, perhaps a slight surge as it figures itself out but hasn't alarmed me enough to pull over etc.

I have a friend with a VAG specialist garage in Croydon so I will probably head there on Saturday to see if he can cast his expert eye over it. I guess I'm being precious but I really love this car and want a good few years out of it so I'm prepared to keep it happy!
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Old 26th June 2017, 02:21 PM
Resolutionary Resolutionary is offline
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Quote:
Originally Posted by MikkiJayne View Post

The misfire could be many things but a common thing on the 2.8 is the cam cover gaskets leaking oil in to the spark plug holes. Worth pulling the coil packs and having a look to see if they're all clean. MAF can also do that although that does tend to manifest as a lumpy idle.
This is the case with mine by the way - I have a leak on the offside bank and you can occasionally smell the burn-off. I think this'll be my first port of call; I'll inevitably rectify the leaky gasket too in the hope it reduces any further issues. The MAF could also be at fault, hence the rev flutter.

Literally drove this thing for an hour before it started worrying me - good ol' Audi!
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Old 26th June 2017, 02:47 PM
ainarssems ainarssems is offline
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Crankcase ventilation hoses/pipes are also prone to failure on 2.8 and could cause the symptoms you experience if unmetered air leaks in.
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Old 27th June 2017, 02:49 PM
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So I went for a brisk drive yesterday and the engine check light came back on.

Same symptoms today but again no noticeable drop in drive-ability. I'm going to see my friend at Tuning Werkes tomorrow afternoon in the hope he can help me diagnose the issues and / or book me in for a proper inspection. I have a bit of a slosh fund ready for the inevitable bills so fingers crossed I can throw money at the situation and it'll improve!

I'll keep you all posted - thanks again for the suggestions.
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Old 4th July 2017, 01:55 PM
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Update! At the weekend I pulled the leads to check for ingress under the cam covers. The verdict - not good.

There was a significant amount of oil in all 6 spark plug holes. I strongly suspect my running issues may be in part due to this, which would not be too bad I suppose (better than a faulty transmission!).

The car is going to Tuning Werkes tonight for open-heart surgery tomorrow, namely:

- replace cam cover gaskets (both banks)
- check coilpacks and spark plugs, drain replace as necessary
- check crank-case breather pipe
- rectify headlight levelling issue (warning light driving me mad)
- check rear suspension and exhaust mounts (clunk / rattle over bumps)
- flush and replace engine oil
- flush and replace gearbox oil if necessary
- flush and replace coolant

Fingers crossed after all this work, the car responds well and is good as it should be. I'll be back!
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Old 4th July 2017, 07:38 PM
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YorkshireBloke YorkshireBloke is offline
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Default Don't mind me but...

Hi,

My expertise is ALL nicked from Brain Boxes on this forum but....

[QUOTE
- flush and replace gearbox oil if necessary
-[/quote]

Maybe read some of the tales of woe on the Forum before you let lose a non-ZF specialist to "replace" gearbox oil....

Robert
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Old 4th July 2017, 07:54 PM
Snaggle57 Snaggle57 is offline
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Had a similar thing with bouncing revs on my 97 a4 2.8 (manual) the cam gaskets always leak on these engines it's nothing to panic about, Had a few v6 models & they all do. the breather pipe replacement is what solved mine, it's very common, mine was full of white gunk so it couldn't breathe, was like cottage cheese in there, it's easy enough to take them off & check & they're not expensive to replace if you need to
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Old 4th July 2017, 09:46 PM
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YorkshireBloke - appreciate the words of caution, this garage has replaced gearbox oil on my previous Allroad 2.7TT and B7 A4 3.2, all good so far - they're VAG specialists in the truest sense!

Snaggle57 - so true about V6 lumps ejaculating oil like it's in fashion. Gets quite tedious though, and I found evidence of sealant around the nearside gasket so I think a bodge has been performed in the past. I too expect it's the breather pipe playing up - would be an inexpensive and easy fix for sure!

I'll let you know how I get on
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