2007 Passat 2.0 TDI Glow Plug light flashing

[jmurray01]

Hi Guys,

Driving home from work tonight (3°C, only down the road from work so engine still cold) I accelerated fairly hard going up a gradient in 3rd to 50MPH then changed to 5th and as soon as I did the glow plug light started flashing and the computer said "engine fault - garage".

It went into limp mode for the 3 miles until I got into town then I shut it off and restarted and it was back to normal again.

Having driven the further 20 miles to my house and trying to get it to do it again I could not and it drove perfectly. Maybe this was because it had warmed up by then?

I know nobody can say for sure without getting it scanned, but is there anything obvious that it could be? I initially thought about the injectors but it has a stamp in the service book to say the recall was done, and from what I've read when they go it is a case of the engine dying completely not going into limp mode. The obvious thing would be the glow plugs and I have noticed it struggling to start a little on these cold mornings, but that wouldn't make a difference to it when running surely?

Having just spent £300 getting the intercooler and hoses changed I can't afford to put it back into the garage again at least not until payday, so I'll see how it goes for the next few days.

I miss driving my old '96 Peugeot 405, it doesn't have 90% of the electrical sensors and switches the VW has and it runs just as well, gets just as many MPG and has never broken down. Why they feel the need to put so many computers into modern cars that then require another computer to read the error codes and fix it is beyond me.

[Crasher]

They put the sensors in to try and stop some of the **** that comes out of a diesel tailpipe.... and still fail!

You need a code read and that is likely to show an overboost problem which normally means a turbo rebuild.

[jmurray01]

They put the sensors in to try and stop some of the **** that comes out of a diesel tailpipe.... and still fail!

You need a code read and that is likely to show an overboost problem which normally means a turbo rebuild.

Bloody hell really, mind you I'm not completely surprised as since having the new intercooler and hoses it has been quite "whiny" more so than before the intercooler went. That's probably why the intercooler broke in the first place if it is overboosting.

It's overdue an oil change but once that's done I'll give it a hard drive once warmed up to see if that clears anything out, as the previous owner did a lot of town driving. It'll either help or blow the turbo completely, either way I'll get an answer!!

[Renars]

Bloody hell really, mind you I'm not completely surprised as since having the new intercooler and hoses it has been quite "whiny" more so than before the intercooler went. That's probably why the intercooler broke in the first place if it is overboosting.

It's overdue an oil change but once that's done I'll give it a hard drive once warmed up to see if that clears anything out, as the previous owner did a lot of town driving. It'll either help or blow the turbo completely, either way I'll get an answer!!

You can also look for second hand turbos, they are getting cheap, but its a bit of a game.

[jmurray01]

Well the issue never came back, and since having the oil changed yesterday the turbo whine has gotten at least 50% quieter, and that isn't just my imagination! It hadn't had an oil change for almost 20k according to the service history so could dirty oil have been affecting the turbo and caused the warning to come on?

Now it had fresh oil I could happily push it harder than before and even on full throttle acceleration up to 4,500RPM it goes with no hesitation, no smoke and no glow plug light, in fact better than it ever has. The only thing I can think I should maybe change would be the fuel filter but that was done at 110k, so how often do they need replaced, since it is on 130k now?

I may still look at changing the glow plugs, as on the few sub-zero mornings we've had over the past couple of weeks it is a bit sluggish starting, and puffs out a cloud of smoke for the first 3-4 seconds which is typical of worn plugs. The only problem is that as far as I have been able to research the plugs are inside the rocker cover (what a terrible design!) and as a novice DIY mechanic that puts them outside my comfort zone. Changing the plugs on my 405 was tricky enough and they are pretty accessible by comparison, except for cylinder 1 which is right behind the fuel pump.

Oh, and one last question if you would be so kind as to answer, does my Passat have a DPF? I don't see a warning light on the dash for it and from what I've read only some models had it.

[Renars]

Hard to say if oil causes that sort of problems it had to kill something. And 20k not that crazy.
20k for fuel filter isnt much.
Glow plugs can be checked and if they are really bad usually there will be error code.
Removing rocker cover isnt a big deal if you want to tackle glow plugs that my be stuck and broken when you try to unscrew and then its a specialist job to get it out.
Most likely it has DPF, what is engine code ?

[jmurray01]

Really I thought 20k was a lot for oil, especially when it also lubricates the turbocharger. I always oil change my vehicles every 6 months/6,000 miles whichever comes first.

I think I'll just wait until next year and then get it overhauled with a new timing belt, new glow plugs and also the filters at the same time.

Not sure on the engine code but I'll try to find out and get back to you. I'm also trying to find the name of the colour so I can get a touch up kit for a couple of stone chips on the bonnet, where would I find that?

[Crasher]

Over the last decade these stupid 20k oil changes have caused incalculable damage to engines and add to that the usual human attitude of “ohh it can wait, NEED those new shoes first” it often gets pushed to 25k, the worst I have ever seen was on a 3 year old Octavia VRS which we could prove had done 33K or more without an oil change, totally wrecked the engine. I ended up buying the car and fitting a new genuine engine and turbo and 12 years/60k miles later it is still a great car that gets Quantum long life 3 oil and filter changes every 3K miles.... the oil still comes out black and smelling nasty even then because all I do is short journeys. I set all my customers cars to 9300 miles/365 days for oil changes.

[DMitch16]

Bought mine in 2011 - full dealer history. Immediately switched to 10k oil and filter changes (twice yearly as I was doing 20k a year). New diesel filter every 20k for a few years, now every 10k as they are £7 each and I buy several when I get this offer price. Biggest improvement (apart from KMB shaft change) - new valve stem seals. Wiped out my oil usage which is now a small top up every few months from a weekly min to max top up.

[jmurray01]

Over the last decade these stupid 20k oil changes have caused incalculable damage to engines and add to that the usual human attitude of “ohh it can wait, NEED those news shoes first” it often gets pushed to 25k, the worst I have ever seen was on a 3 year old Octavia VRS which we could prove had done 33K or more without an oil change, totally wrecked the engine. I ended up buying the car and fitting a new genuine engine and turbo and 12 years/60k miles later it is still a great car that gets Quantum long life 3 oil and filter changes every 3K miles.... the oil still comes out black and smelling nasty even then because all I do is short journeys. I set all my customers cars to 9300 miles/365 days for oil changes.

My thoughts exactly! As I do long journeys (25 miles to work and 25 back on a daily basis) 6k is fine but for my mother's car which mainly gets used around town I do every 6 months regardless of mileage so normally works out at about 2-3k.

The way I see it is that oil is cheap, engines are expensive!! Better safe than sorry.