I wondered if anyone had come across this issue, which mainly affects the 1.2 litre 3 cylinder VW models such as Polo.
A year or two ago my old boss had a misfire on her 2003 Fabia (Same engine). She chased her tail with various garages who did guesswork diagnosis and spent hundreds on coil packs, plugs, fuel injectors, before asking me to look at it.
First thing I did was a compression test and found only 20psi in cylinder 3. Upon removing the head, and inspecting the (all six!) valves, I found number 3 exhaust valve was burnt out. I bought new valves from eBay and did a top end rebuild on it for her, and it ran lovely after that.
I've done some internet research, and it appears this is is a very common issue. It's suggested that it can be caused by poor valve guides, however the guides on the one I rebuilt, at least FELT ok! There are scores of Polo owners on the net complaining about the exhaust valves on cylinder 3 burning and cracking.
The reason for digging this up and thinking about it, is that (through boredom) I have seen for sale very close to me, a 2005 55 Polo 1.2, advertised as MOT failure, can't pass the emissions test due to engine misfire.
If it's this valve issue, it's actually a pleasant job to do, and I'm considering buying it to keep as a bit of a project to play with for when I am recovered a little more (or until I can find a willing apprentice
) - although it's a timing chain setup, it's straightforward to understand and being a half-engine, the components are all lightweight etc.
If you have any experience of why this fault happens, please share! I'm guessing LPG, in light of the issue, would be a big no-no!
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Topic: VW Polo - Burnt out valves (Read 1837 times)