Remap

[Vrslad]

Hi peeps, I have a mk2 octavia vrs petrol, im using it as a taxi, im thinking of a remap, but im worried about the longevity of the engine, ive had it around 8 months, and as I said in an earlier post, I have to put around a litre of oil in, every 1000-1500 miles, its currently on 65k, and I plan on keeping it for 3-4 yrs, I average around 40k a year, its always serviced on time, and any knocks or bangs are sorted straight away, is it worth a remap

[MarkyG82]

From many accounts on here they map well and you may see a return on fuel economy with the high miles and steady driving.

But... I would deal with the oil issue first. A map could make it worse and that's the last you want from a taxi.

[Ootohere]

Better address the excessive oil use before Remapping it. 

You are using excessive amounts of oil even if VW / Skoda say may use 0.5 litres in 1,000 km. (621 miles)   eg 1 litre in 1,242 miles. 

[Vrslad]

Short of replacing the engine, there's not alot I can do, luckily I have a good mate who I get the oil from at cost price, have spoken to skoda and others, i've done around 20k so far with no issues, I check the oil every monday and thursday, and top up accordingly, at least it has fresh oil every week lol

[Ootohere]

Are you now using 5w 40 FS to VW502 00 rather than 5w 30 FS LL type rubbish?  Just to try help reduce the oil consumption.

[Vrslad]

Yep, its just 1 of those things, there was a batch of dodgy engines as such, that affected some models, some vw's have the same, along with the seat leon and cupra, and because the oil consumption is well within the set parameters, there's nothing they will do, at least im only paying around £3 a litre, and its tax deductible lol

[shyVRS245]

Like the other guys have already given you good advice, wouldn't map it as it may make your oil usage worse. Mine used about 1.25 litres over 18,500 miles, but since it's first service last month has used no oil so might be settling down or I'm not booting it quite so much. Just reached 20,000 miles this weekend in 18 months.

[Ootohere]

@Vrslad,  where do you get the idea that well within a set of perameters?    There is nothing the 'whoever' you speak of will do, 

but as for 0.5 litres in 1,000 km, (621 miles)  that is not a 'perameter'  just a VW group figure and a load of nonsense. 

 

The Invoice on an Oil Consumption test below is also nonsense as the Tech got the weight of a litre of oil wrong it is not the same as H20.

So the result was wrong, and the car did get a new engine, but then it was under warranty.

*Note how it says ''within the specification of the manufacturers guidelines'  because that is what VW / Skoda have 'Guidelines', try and get the 'Perameters' in writing...

Edited 24 February, 2019 by Skoffski

[Vrslad]

In the owners book it says, some engines will require up to a litre of oil every 750-1500 miles, I did ask about an oil compression test, but I live over 20 miles away from the main dealer, plus its used as a taxi, so if the amber warning light comes on, I'd have to top it up to get the car back to the dealer, so no go

[Ootohere]

Which Owners Books?  The bit above from a manual has been the same for years for 3,4,5,6,8 & 12 cylinder petrols and diesels from 44kw.

0.5 litres in 1,000 km. 

 

As it is you posted you are about at that amount, just not crossing Alpine Passes in High Summer with a full car and towing a horse box, just doing some 'driving for work' in the UK.

 

If just topping up works and no plug fouling etc then that is as good as it gets without spending a few hundred quid.

Edited 24 February, 2019 by Skoffski

[stever750]

I had a mk1 vrs petrol that behaved like a 2 stroke. I got it remapped by Shark and no change to oil consumption or wear. Just make sure it is regularly checked. At least you know its fresh oil circulating around, rather than stuff that has been there for 18k or so miles slowly degrading!

[stever750]

Fwiw, this car was still running at 150k miles 

[EnterName]

On 08/04/2019 at 17:04, stever750 said:

I had a mk1 vrs petrol that behaved like a 2 stroke. I got it remapped by Shark and no change to oil consumption or wear. Just make sure it is regularly checked. At least you know its fresh oil circulating around, rather than stuff that has been there for 18k or so miles slowly degrading!

I know it's an old thread but...

Just a thought , but I wonder if when an engine "uses" oil, it does not use it perfectly.

By that, I mean assuming it's burnt, presumably the most volatile constituents of the oil are burned off most easily, and there's less volatile constituents that don't burn so easily.

 

Where I'm going with this, is that I suspect when an engine burns oil, it leaves some crud behind.

You add more oil as it is burned by the engine, and slowly more non-volatile crud builds up.

 

I've no idea whether my suspicion is correct, but I'd love to know where the "used" oil actually goes..

Maybe oil that gets past the piston rings is either burnt in the combustion process or flung out through the exhaust?

Maybe it really is nearly all perfectly burnt, and what's left is negligible?

Maybe it's all dealt with by the PCV (Positive Crankcase Ventilation) system?

 

I dunno, but maybe someone else does. (Probably @weasley, who has decades of experience with engine oil.)

[weasley]

Good question.  In basic terms the oil is consumed in three ways:

 

- volatility; as you say the lighter molecules evaporate and leave the engine through the crankcase ventilation, so into the intake air and burnt in the combustion chamber.  This is not “burning” of oil, just evaporation.  It is driven by the volatility characteristics of the base oils in use.  The test used to identify, compare and control volatility is called the ‘Noack’ test, which is run at 150°C.  Specifications tend to limit this to 10-13% volume loss maximum

 

- combustion; oil gets past the piston rings and is burnt in the cylinders. Not a lot you can do about this from an oil perspective, driven almost entirely by engineering

 

- oxidation; the oil gets hot in the presence of oxygen and is oxidised (“burnt”).  The by-products of this are all sorts of things - acids, water, carbon etc.  This tends to lead to oil thickening - it can be controlled by using robust base oil and antioxidants.

 

The ratio of these is dependent on the engine, operating conditions etc but will be split mostly between volatility and combustion, with much less oxidation.  The volatile components are mostly from the base oils, so this has the effect of concentrating the additives but obviously reduces the amount of fluid left to lubricate and also leads to a thicker oil.  Combustion affects all of the oil and is what causes issues with DPFs as additives are burnt, forming ash which blocks the DPF (and now GPF).

 

Topping up the oil has two fundamental benefits: the first is the increase in available volume of oil to do the job and the second is an addition of fresh additives (antiwear, detergents, antioxidant etc) to help refresh the oil.  Oil change intervals are determined with all this in mind so that the oil should still be serviceable when it is finally drained and replaced.

[Ootohere]

 

https://onlyrevo.com/blog/1-4-tsi-twincharger-known-engine-issues-to-be-aware-of

 

The Elephant in the room that VW Group just ignored with the 1.4 TSI / TFSI 132-136kW Twinchargers 2009-2014/15 is Borewash.

 

VW Group never admit to it, or that Long Life oils and Super unleaded petrols can be an issue,  just how much detergents does an engine require?

 

Funny how the Superunleaded even over 100 octane is not really an issue if you do not use the Oil VW Group Recommend.

Also funny how remaps were better than the Mapping / Engine Management that was & is OEM with the Twinchargers. 

  Not REVO's though, they got theirs wrong. They were as bad as VW at owning up to that.

 

Over 25% of the CAVE engines had failures and like for like replacements failed as well.

VW Group changed mapping, breathers, oil spray jets and discontinued the engines after 3 years and still had issues and again played about with mapping.

All through this it cost many owners lots of money when they had no warranty cover and even those that VW Group sold extended warranties to then they claimed 'Known issues'. 

There were known issues and the Management / Seniors / Engineers know who was to blame, it was them.

A CEO who was an Engineers Engineer.  As in Deaf Dumb & Blind to being the person signing the engines off.  Like with the Defeat Devices as well.

 

 

Edited 26 June, 2021 by e-Roottoot