MegaSack DRAW - This year's winner is user - rgwb
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Car is hardly being driven at all at the moment and never over 60 mph. EGR?
This one?
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if so -
https://www.yourmechanic.com/article/is-it-safe-to-drive-with-the-glow-plug-light-on
On briefly when you start means your glowplugs are active, on while the engine's running means there's a fault.
Yes that one. Car went into limp-home so I drove it to an independent who told me it was mouse damage and showed me a horrible pic of two chewed vacuum hoses. When I checked under the cover this morning there was plenty of mouse damage but no new hoses and none that looked like the photo. So I'll be nipping back for a word next time I'm in town.
The annoying bit is that that's an hour's drive now instead of 10 minutes up the road and a quick bike ride home as it was in Lancashire so it means taking two cars. How I'm hating this, we've thrown away all the convenience of living near a town.
Anyone care to guess what the fault is?
No idea, worse case is injector failure (mouse stuck in there!?)
Google “glow plug light Passat” and you should find owner forums with info.
That coil light means an engine fault related to emissions. So it could be quite a few things related to emissions. On mine (2006) the turbo vanes are operated via vacuum, so you could easily get a boost issue via mice eating hoses. EGR valve is electrical, so that won't be hose related but there could equally be other wires chewed through. But you cannot guess, you need codes read.
How I’m hating this
There will be upsides, don't worry.
Check the brake lights.
The annoying bit is that that’s an hour’s drive now instead of 10 minutes up the road
That's a pretty serious limp mode 😉
I had this on a 1.9 tdi years ago, it was a failed glow plug. They can be found down the back on that engine so fiddly to change.
Failed glow plug won't cause limp mode. My money's on turbo vanes.
What year is the car?
Strangely mine did (2005 Polo GT), I dropped it off at the dealer thinking it was something more serious. They told me what it was and I said change the others whilst you are there, only thing on the bill was diagnostic, 4 plugs and labour.
Mine did that but didn't go into limp mode. Faulty sensor apparently. Been OK since.
It's a 2016 2.0 tdi
I'm beginning to think it's been a bit slow to start recently.
Where are you I've vcds happy to plug it in.
My old Golf TDi had the same symptoms a couple of times. First time it was the EGR valve, second time a faulty fuel injector. Both a bit of kick in the wallet.
Could be a number of root causes - need a vcds to get the codes read.
My Puggy Partner did similar, an engine clean sorted it but the clean was extensive, not just an Italian tune up... saying that I don't know what was all done but bits of the engine were removed and cleaned.