Pre-emptive Diesel Engine Maintenance

[Paynewright]

Since joining the forum I have read numerous threads of woe concerning significant / costly engine issues. I wonder if there is anything we can do, to be ahead of the game and prevent an inconvenient breakdown or change one part prior to failure that can negate another more expensive repair.

My van is a 2018 102hp 5 speed BMT 2.0 TDI CXGB, manufactured late 2016. Currently on 24k miles.

So far I’m doing interim oil changes (so 5K intervals) and keeping the Ad Blue tank topped up to hopefully avoid crystallisation on the sensors. Also using Millers diesel additive.

My current thinking is to fit a new EGR assembly at around 50k miles (leaking coolant via cores) and instantly have it mapped out / fit an emulator. Also, remove the DPF and have it cleaned / back flushed (this blocking seems to cause sensor / turbo failures). Fit updated EGR flexi pipe.

I know there are a few diesel engine experts on the forum, some advanced level at diagnostics and also some brilliant DIY mechanics so wondered what thoughts / ideas you had.

Might be useful to break down the suggestions by engine type.

 

[DaveD]

It's an interesting idea, I'm certainly not an expert but regular oil changes (forget what VW say about long life service intervals) must surely be the most cost effective way to prolong engine life, especially if you DIY it.
I'm not convinced that replacing the EGR assembly at 50K miles is cost effective unless you have evidence that it is leaking coolant or is defective in some other way. I don't regard an EGR assembly as a service item.
Some people seem to have DPF problems, others don't, personally I've never had any issues on any of my diesel vehicles so I'll leave well alone!
On any Forum you read about the minority of people who experience problems, not the thousands who don't, there are a lot of these vans running around reliably on high mileage on their original mechanical parts.

 

[Paynewright]

I get what you are saying about internet hype and sample sizes (I was a data analyst for a few years!). I’ve previously owned an Impreza and currently have a 996 911 - if you read all the horror stories you’d never buy one but actually only a small % of production volumes have catastrophic failures!

I just don’t like the thought of a failure affecting a long planned epic holiday. £400-500 on an EGR assembly seems cheap peace of mind Vs a £4-5K holiday using the van.

 

[DXX]

All EGRs are going to block eventually, some will be replaced and others will be blanked and fitted an emulator fitted.
Regular oil analysis will allow condition monitoring of the engine and eventually if the data input is correct you can evaluate what the optimum milage between oil changes is for your engine / driving profile.
Turbo friendly driving maybe one of the best methods of prolonging engine life at zero cost. Booting a cold engine and stopping the engine (stop / start included) shortly after high rev’s is certainly not good for turbocharger life.

 

[Paynewright]

I’ve always wondered about stop/start Vs turbo cool down. I always switch the stop/start off when pulling into motorway services! (Hangover from my impreza ownership where turbo timers were common fitment!)

 

[DXX]

I’ve always wondered about stop/start Vs turbo cool down. I always switch the stop/start off when pulling into motorway services! (Hangover from my impreza ownership where turbo timers were common fitment!)

Exactly, cooling is one issue but lack of oil pressure at engine stop with maybe 20-50K RPM isn’t great for longevity.

 

[mark]

I just drive mine, ( 17, 204 dsg )will worry about a breakdown if and when. Currently on 130K - the DPF is almost full but thats expected at the mileage. Took out the 5 year warrenty as well which turned out to be a waste as it's never had any done...

Just posting this as a counter to all the breakdown posts which forums tend to fill with.

Cheers.

 

[JFWerkstatt]

My 2.0tdi suffered EGR failure at about 130k, bill was £1500 inc a cambelt and waterpump. Worthwhile I’d say, especially as the things get a little older.

 

[TrevorK]

After the High Pressure Fuel Pump failed on my son's 2litre Audi A4 at around 130k miles (effectively writing the car off with a £5k repair estimate), I did some Googling.
It does seem that failures are random, but seem to increase in vehicles with over 100k on the clock, so wonder if HPFP should go on your list Paynewright?

 

[Paynewright]

Not at £5k

 

[DXX]

5K is the price when the damaged pump takes the injectors with it. Even more if the cylinders are washed dry from leaking injectors.
It would seem like a good idea to renew the HPFP.
Contamination is the enemy of sensitive systems such as fuel and hydraulics. In my experience human intervention is a major cause of contamination.
Just because you can see the dirt doesn’t mean it’s not dirty. Trust your expensive engine to somebody with more than 3 brain cells.

 

[TrevorK]

Not at £5k

£5k if the HPFP fails. Pump seems to be around £1k.

HPFP Failed. VW Want Nearly £6k

3 weeks ago my van failed to start. Vw assist came out, diagnosed and no fuel pressure at the injectors or high pressure fuel pump. I know the hp fuel pump failed and they are the single most unreliable thing in today's cars. Transported to vw in Notts. It took them 3 weeks to get a fuel...

www.t6forum.com

I am sure others know better than me.

 

[DXX]

£5k if the HPFP fails. Pump seems to be around £1k.

HPFP Failed. VW Want Nearly £6k

3 weeks ago my van failed to start. Vw assist came out, diagnosed and no fuel pressure at the injectors or high pressure fuel pump. I know the hp fuel pump failed and they are the single most unreliable thing in today's cars. Transported to vw in Notts. It took them 3 weeks to get a fuel...

www.t6forum.com

I am sure others know better than me.

A damaged pump distributes debris into injectors, damaged injectors no long meter fuel / seal, cylinder wash, fuel dilution of engine oil…….
So when changing a fuel filter and using a piece of dirty rag or priming it with some ‘clean’ fuel it can cause a huge amount of damage.

 

[Lukavell]

I think 5k oil changes are a pretty safe bet. I've just bought a kit for £55 with 7 litres of oil, new washer, sump plug and filter. Pretty cheap maintenance and well worth it. My Dad used to have Renault Megane Scenic which he changed the oil on every 5k, it ran like a sewing machine - ugly as sin though!

 

[Hamster67]

Very interesting thread, not least because I have an identical spec van but with 80k on the clock.

I am having coolant issues, I'm not losing any but there is a strong urea smell coming from it, it is sticking to sensors and giving faults.

I had a 30 minute flush, smell is still apparent but not as bad, my next step is a second flush and coolant tank replacement, mechanic recommended mapping out the AdBlue which he feels is related.

If you are looking for preventive maintenance tips search ' silica bag in coolant' on You Tube. An easy fix to prevent a potential problem caused by a bad idea from VW.
 

 

[Paynewright]

Silica bag already removed!

 

[huw169]

Err, first I’ve heard of this. Did a little research and I’ve concluded that VW are morons on this one.

On the T6 where is the ‘Mit Silikat’ printed on the expansion tank? I can’t see it so hoping I’m clear and VW saw the error before making mine, but would like to be sure. Thanks

 

[Paynewright]

The bag in the coolant is a bit difficult to spot as its all pink! I posted some pictures on the forum when I did mine!

 

[huw169]

The bag in the coolant is a bit difficult to spot as its all pink! I posted some pictures on the forum when I did mine!

Thanks, but the actual expansion tank has ‘mit silikat’ on it if the bag is inside apparently. Did yours have this and where was it stamped/printed? Was it obvious?Mine is not obvious.

I’ve read the silica bag is likely to be sealed in between the inner and outer skin, and I’ve seen a video of a golf where this is true.

It’s chucking down and cold and dark outside so I’m opting for the dry research method rather than braving the elements.
Thanks

 

[Paynewright]