Hi,

I think I have some variation of "the old 17608 problem". The engine management light hasn't come on recently but went through a period of coming on quite frequently, for a few days at a time, a month or two back when the weather was colder. Other symptoms:

• When Des read the fault codes for me about a month ago (thanks!) I had a 17608 and 17535. The dealer's memo cites 17608 and 17545 (different number but same description) as evidence of "that problem".
  
• When the engine is cold there is a flat spot at around 1500rpm, causing lumpy acceleration from stationary (it's only really noticeable in 1st and 2nd gear). When I start the engine in cold weather it's so pronounced for the first minute or so that getting across the main road on my way to work it a bit of a test of nerves. Despite the recent warm weather, it seems to be is getting worse. Does this point to the leaky intercooler pipe?
  
• Since I bought the car, about 6 months ago, it has made a fluttering sound when I lift my foot off the accelerator suddenly (e.g. changing gear while accelerating, although it still does it when not in gear). It sounds like boosted air bouncing back off the throttle plate and stalling the turbo, suggesting the DV or N249.
  

The car's due in for a 60k service in a couple of weeks and I'm not sure which bits to ask them to replace. The mechanic (at Whitehill Skoda, Meopham) said that 90% of the cars he's seen have been fixed by replacing the intercooler pipe. The fluttering makes me think it's the DV or N249 valve, though, but I don't know which one. Could one component failure cause both the above symptoms, or is it likely a combination?

I'm on a bit of a budget so I'm not really interested in uprating any components unless the standard part is known to be a a weak point.

Update on the fault codes: 17545 (the usual one) is additive trim; 17535 (my one) is multiplicative. (Source)

I'm running on LPG so I think multiplicative trim can be safely ignored: It doesn't burn quite as easily so would need to run slightly richer.

Nobody...? :(

I'm assuming you have a 1.8t in you Octy, so I'm going to suggest you start by changing the spark plugs and/or your dump valve (latest part # (tt225) 06A 145 710N). If you car is unchipped, then oem spark-plugs should do. If it is chipped, try some of the plugs I mention in my thread here. It is a cheap place to start as you can get some adequate plugs, recommended by tuners for as little as £10 for a set of 4!

I had a coil pack go a couple of weeks back, and after a new one I couldn't accelerate smoothly up through 3k-5k rpms (especially in 3rd gear). I changed my MAF @ £70 (ouch!) only because after changing the coil pack I'd also cleaned the old MAF and air filter and was worried I'd damaged the old one (which I hadn't :( ). So, I read around on the net's "1.8t"/Vag forums, and amongst torn/flatten inlet/intercooler pipes, replacement n75|n249|n112 and oem dump valves, the issue of spark splugs came up quite a bit. Changed mine out this morning, took here onto the M1, pulls like train!

Hope everything turns out Ok for you.

Cheers

Rich

P.S. Also keep in mind the "Ignition amplifier" on AGU engines (can cause misfire issues). Not cheap (~£220), see thread here.

My plugs have only done 20k so I'd have thought they'll be alright - wouldn't they? How much hassle is it to dig them out (as in, several bolts or a couple)? One thing I'm rather short of is time, at the moment.

The car's due for its 60k service on Monday and I've asked them to replace the DV and N249 valve then. I'll let you know what happens...

Hi,

I'll apologise in advance, this is pretty long winded :P

Since posting, I've come across a few more possibilities (I am going to put together a post specially, I think it will be of interest to many).

Anyway, I cleared down the 17608 I had (diagnosed by AA, on a 2nd call out, after a coil pack replacement) and basically, the N249 was having trouble opening my dump valve (DV). A visit Farmers Skoda Leicester, and they agreed that a lot of 17608's were down to the DVs (so hold back on the N249 if not under warranty) I've got a Bailey DV30, so I rebuilt it using LM2 lithium grease. I tested its ability to hold vacuum by pushing the piston upwards and then covering the hole with my thumb (the vacuum held). Unfortunately, this wasn't the end of my problems.

I changed the sparks out Saturday morning, and everything seemed to go well (the car accelerated like new), at first. In the afternoon, after I'd posted that all was well, I went out again. Surging was back again :eek: ! I did some more googling and I came up with 2 ideas.

1) The coil packs are popping up (initially sounds silly, huh?)

2) The coil packs ordering may need to be 'rotated' (i.e. put cylinder 4's coil into 1 etc.).

Now, I've got TONS of info on #1 (I'll post later), basically, some 1.8t VW engines (TT 225 for one) use bolt down coil packs, which I'm guessing is to handle the extra boost (my car is Jabba'd). Some guys in the USA have fabricated brackets to alleviate this on Bremi-branded coil pack installs. Now here's the interesting bit. I swapped my new AA-replaced coil pack in cylinder 4, as in #2, for cylinder 1's coil and my car has run like a dream for about 100 miles now (no flat spots)!!! For me, it has been as simple as that. I now have access to some diagnostic software (odbguage, on palm pda), and the are no error codes whatsoever. So, maybe you'd like to swap round a coil pack or 2, cylinder 4 is supposedly often the culprit (don't ask me why, I just read it). You may need a 5mm Allen key, 10mm socket to remove the bracket/reservoir, and your fingers/flat head screw driver to pop the coil up (they're like lego, really).

Sparks are easy to replace (16mm socket wrench and copper grease), coil pack removal is childs play, so have a go .

All the best

Big Rich

First Ive heard about this rotation, but if it works...

See DGW's tutorial on coil pack removal.

Rich

I had my 60k service done last week at Whitehill Skoda, Meopham, and also had the N249 valve and "that" intercooler pipe replaced.

The mechanic also checked the diverter valve itself and said he couldn't fault it. I was a little surprised as I'd asked him to change it but I do trust the guy - he's one of those mechanics who actually enjoys tinkering with engines, rather than just doing it to earn a living.

I didn't have the plugs changed as they weren't due (and it was a lot of money to spend in one go anyway!) but I'll keep them, and the coil packs, in mind.

The car feels a bit better - no flat spots and no CEL - but I won't really be able to tell until I get another frosty morning.