LC running on two cylinders

[Fluff]

Hope you guys can help - my LC has briefly run rough a few times over the past week but quickly cleared itself. I put my fault code reader in the car expecting the problem to return and this morning it did, in a big way - the car drove like a lawn mower and I only just got to work, crawling along at 20MPH max. I plugged in the code reader and got this:

16684 = PO300 Random/multiple cylinder misfire detected.
16687 = PO303 Cyl 3 misfire detected
16688 = PO304 Cyl 4 misfire detected

I immediately suspected coil packs (although I replaced all four with 'L' types only 9 months ago) and put in two of the good 'H' types I'd taken out, which made no difference whatsoever. The plugs look fine and were replaced at the 5 year/60K mile service 3 months ago.

Do coil packs go in pairs? My last one didn't - I was given the option of replacing the faulty one or the whole set and having read on here about how poor they are I decided to replace them all. But surely the new ones haven't packed up already? And could my 'good' old ones have packed up in storage?

Another worry - by driving the car on two cylinders have I gunged up the cat with unburnt fuel?

All ideas appreciated!

TIA,

Fluff

 

[Saul]

it could well be a lamda sensor problem, and/or MAF issue

you either need to set about some diagnosis yourself or get it looked at by a professional (will need VAG COM)

 

[Nathanio]

HT leads?

 

[DPJ]

Probably as Saul says.
You could try clearing the codes and switch 1&2 coilpacks with 3&4 - see if the problem moves....

 

[Fluff]

Thanks for the replies.

The Lambda was also replaced not all that long ago. Pardon my ignorance but what does the MAF do, where is it and how easy/costly is it to replace? Come to think of it that has been replaced before as well, under warranty. IIRC it just caused a loss of power but the engine still fired on all four.

No HT leads to check - the coil packs are wired directly into the loom!

I like the idea of swapping packs around - will try that at lunchtime.

I love this car but why are so many minor components so damn unreliable? "Nothing is as reliable as a Volkswagen" my 4rse My crappy old Rover never ate any coil packs, sensors or senders in 100,000 miles . . .

Fluff

 

[Nathanio]

Oh yes of course being a derv driver I don't know too much on the 1.8T

 

[Fluff]

S'okay Nathiano

Haven't had time over lunch to do the swap thing but called the local VW Stealer about getting some more CPs:

Them: "What's the part number boss?"
Me: "06B 905 115 L"
Them: "Ah, that's been superseded by 06B 905 115 R"
Me: "Does that mean they might last more than a year?"
Them: "I hope not chief - I sell loads of 'em!"
Me:

So where do I get these Hitachi CPs I've been hearing about?

Fluff

 

[RobM]

So where do I get these Hitachi CPs I've been hearing about?

Fluff

According to the thread on this page of this forum dedicated to that specific product.... either from VAGParts or a US supplier.

 

[richybigman]

Me: "Does that mean they might last more than a year?"
Them: "I hope not chief - I sell loads of 'em!"
Me: Fluff

That made me chuckle

 

[Fluff]

It did me as well, I must admit . . . once I'd calmed down

Tried DPJ's idea and the engine fired up on all 4 But sure enough after a few minutes it was misfiring and the fault codes were 16684 and 16686 - cyl 2 now playing up. I expect cyl 1 is trying to make its mind up.

So a new set of coil packs for me then, the second in 9 months. What a pile of shoyt

Anyone know where I can get the Hitachi coil packs over the counter or delivered by courier tomorrow, so I don't have to do without the car all weekend

Fluff

 

[RobM]

You've left it too late for delivery now. But if you read the other post on these Hitachi coils, you'll see that RobDon posted the part numbers for them so you can buy direct from Audi. So grab those and head to your nearest Audi dealership.

 

[Fluff]

My local Audi dealer did indeed sort me out with 4 X 06B 905 115E coil packs @ £25.45 each + VAT on Saturday morning. I'm sure they can be had cheaper but I was just glad to get them at all Mine didn't come with the M6 X 20 bolts/machine screws (8 needed) but I had plenty in my stash. They won't work without being bolted down either as the contact to the plug terminal is a short coil spring rather than a push-on clip.

Incidentally, the price was the same as the VW dealership comedian quoted for the 06B 905 115R German made Bremi units.

Car now running great again - thanks for the help guys

Cheers,

Fluff

P.S. I think I saw on another thread that changing plugs is recommended in conjunction with new CPs. Is that just because they're accessible at the same time or is there a technical reason? I was quoted £12.00 each for the NGK plugs and as they were (supposedly) replaced at the last service a few months back I politely declined. Halfords tried to sell me a £20 set of Champion Eon plugs that their app. book recommended, which I also declined. Did I do the right thing?

 

[ChrisJ]

I know what you mean matey, i have had a few minor issues since the remap on my 1.8T. They told me once i had done it, any dodgy sensors or coil packs would fail if they were going to atall!! lol

I have replaced 1 coil pack and a temp sender sensor so far but im pretty sure another coil pack is on its way! as i have a slightly uneven idle, i am actually ordering another 2 coil packs shortly to keep in the boot!!

But i hardly think this is a negative for the car, as it's such an exciting drive and very good all round car.

 

[Fluff]

<< it's such an exciting drive and very good all round car >>

You won't get any arguments from me on that score Chrissyboy

I do find it odd though that the 'good' Japanese made Hitachi coil packs are only specced for Audi models and the smeggy German made Bremi CPs are considered good enough for the rest of the VAG range when they are a known weakness.

I know it's not a cheap option but I'd be inclined to replace your CPs as a set if you know they're weak - if my experience is anything to go by they seem to set each other off once they go

Fluff

 

[Pabs]

People....

How do you know which cylinder is which?

I had my spark plugs changed yesterday, and i've got a coilpack gone now (i think)...


16684 - Random/Multiple Cylinder Misfire Detected
P0300 - 35-00 - -
16688 - Cylinder 4 Misfire Detected
P0304 - 35-00 - -

I just need to know which cylinder is #4 - is it the one under the vac reservoir??? (which i suspect it is, sods law dictates)

I'm off to the garage to get a new one asap - apparently R is the latest revision.

Cheers peeps

 

[Big_daddy]

well when i had my changed, the garage stated to me From 1 is on the left and 4 is on the right.