Tiguan 118TSI cracked piston

[Ryan_R]

Well the plan is to upgrade to an Audi perhaps in early 2015, so that's potentially 6 months out of extended warranty, I'll let you know how I get on

I've joined the two wheel club now as well which so far is proving to be a much better option for commuting.

[AdamD]

I have heard (no hard evidence) that the stock software runs the engine quite lean. Gets good economy but runs hot and can result in the damage we're seeing.

I've read some detailed analysis that found that the standard tune for the engine (in the Golf 118 application) runs aggressively lean in the first couple of minutes of cold startup, to rapidly heat the cat (which is far more efficient in cutting back on emissions when hot). It's those first couple of minutes on every cold start that I'd be most concerned about with this engine.

[Ryan_R]

I can somewhat vouch for this - on some occasions when I cold-start the car it runs quite rough for the first minute. I've recently added the Misfire stats on my MFI and whenever this rough shuddering behaviour occurs, I see a load of Misfires on Cylinder #4. Usually in the vicinity of 25, but this morning I saw 45. Not bad enough to log a fault code or show the engine fult light on the dash though. Might have to quiz the dealer on it, but I know Aaron's cab shows the odd Misfire as well.

[patchwick]

Just out of curiosity OP, how did it run when it was diagnosed with a cracked piston? and any particular codes?

My Tig are throwing codes for cylinder 1,3 and some intake code which I could not remember. Atm we think its just the coils or the spark plugs which I'm about to replace soon.
The CEL light disappears randomly for some reason and goes back after couple days.
Also it drives fine but there are times that it won't rev past 3k when driving (not stationery)
Will try and do a compression test now I've read your story.