TSi fuel economy

[GWoodhouse]

The infotainment system may be crap but I can't fault the engine! Disappointed my mpg dropped below 56 due to rubbish commute home this evening.

[Gerrycan]

45 minutes ago, GWoodhouse said:

The infotainment system may be crap but I can't fault the engine! Disappointed my mpg dropped below 56 due to rubbish commute home this evening.

 

What size engine and transmission type?

[GWoodhouse]

11 minutes ago, Gerrycan said:

 

What size engine and transmission type?

1.5 manual

[avi4tor]

Also a 1.5 manual - I recently did a trip from the NorthEast to SouthWest Wales.  When I got to the M6 I was averaging 64mpg (150 miles).  Unfortunately the welsh roads did for me and it was down to 60mpg by the time I finished.  However it only used less than 1/2 a tank - so I did the outward and return trip on one tankful.  Now if I had been foolish enough to get a battery car, how many stops would I need? how long would I have to sit and wait in total in order that I could complete the journey?

[SteveTheElder]

Yep, the economy in the 1.5 manual is much better than I expected / was hoping for.

Over the 27k miles I’ve done mine it’s averaged over 57mpg.

This evening I had a run to Heathrow T2 and back (M3, M25, M4, plus short-stay car park faffing), trip computer reckoned on 67.4mpg.

[Gerrycan]

Not everyone will agree with my personal opinion that the smaller capacity tsi engines have for many years offered a better balance of power/economy than the larger 1.8 and 2.0tsi engines, as I have never needed to use the full potential of my 1.4tsi on the road.

 

The mk4 Octavia has class leading aerodynamics and the 1.5tsi with variable geometry turbo and cylinder deactivation is one of the most sophisticated (complicated?) production ICE engines so no real surprise with the excellent figures quoted especially on a longer (UK summer trips).

I believe the cylinder deactivation activates over 1500 rpm and under 30% available torque in Eco, which would be 90+% of my driving. Do the 1.5tsi owners notice the difference?

 

The quoted figures are measurably better than I could probably achieve in similar circumstances with my 2014 manual 1.4tsi but not enough to justify the expense of upgrading even if it was available in Australia. Our Mk4 Octavia is limited to 1.4tsi with 8 speed Aisin torque converter box below the 2.0tsi options, no manual version at all 😞 .

I prefer manuals, not that you have to change gears much at all on the open road due to the oodles of low down turbo torque and the relatively light body.

 

Out of curiosity does anyone know if the 2.0tsi 'Budack' cycle engine is still in the Skoda range and if it actually was more efficient and whether there is a 2.0tsi with cylinder deactivation? 

 

[avi4tor]

47 minutes ago, Gerrycan said:

Not everyone will agree with my personal opinion that the smaller capacity tsi engines have for many years offered a better balance of power/economy than the larger 1.8 and 2.0tsi engines, as I have never needed to use the full potential of my 1.4tsi on the road.

 

 

I slightly disagree.  I used to have a 1.8, and it was more flexible and an easier drive.  With the 1.8 I would do most driving in 5th and 6th gears, with the 1.5 I have to drop to 4th much too frequently.

[Gerrycan]

5 hours ago, avi4tor said:

I slightly disagree.  I used to have a 1.8, and it was more flexible and an easier drive.  With the 1.8 I would do most driving in 5th and 6th gears, with the 1.5 I have to drop to 4th much too frequently.

Interesting, I honestly cannot remember anything being written about the 1.8tsi in manual versions. Never read any really notable consumption reports from manual or auto versions either, so I sort of discounted it because of that.

While I think my 1.4tsi is very tractable it is possibly quite low geared compared to the 1.5tsi. As near as I can tell I'm doing about 2700rpm at 70mph in 6th gear, allowing for the known inaccuracy of the speedo and unknown tachometer accuracy.

Edited 26 July, 2023 by Gerrycan

[SteveTheElder]

@Gerrycan in my 1.5 manual, 70mph is at ~2350rpm (60mph is dead on 2000rpm, so 30mph per 1000rpm) in 6th gear. Compared to my previous car, a 1.4tsi (125ps) Superb Mk2 hatch (manual), the 1.5 Octavia is notably less flexible/tractable at low rpm requiring 2nd for some roundabouts whereas 3rd was fine in the Superb; over 56k miles the Superb averaged 48.9mpg - I was expecting similar from my higher powered (150ps) 1.5tsi but its returning about 15% improvement. 

 

The cylinder deactivation in the 1.5 must contribute something towards that improvement but how much I wouldn't have a clue! I have seen the deactivation cut in at 1300rpm pottering around town in Normal Mode, not aware of it being more active in Eco though logically it would be - I'm now intrigued so will have to check it out.

[TheUltraRunner]

I just came back from 10 days road trip through Wales and UK. As a hire car we got a Seat Alteca FR with 1.5 TSI engine (we got a free upgrade from a Peugeot 2008). I believe it's the same engine. And I was really surprised at the fuel economy considering the size and the aerodynamics of the car. We did 1600 miles and the average was 46 mpg. I would say this is quite good for such car. And it could be even better since I'm quite dynamic driver. 😁

[avi4tor]

I checked the rev/speed on my 1.5 manual combi this afternoon, and in 6th gear doing 50mph (checked against a gps receiver) the engine was doing 1500 rpm.  So 60mph would be 1800 rpm.

Edited 26 July, 2023 by avi4tor

[UrgyMcKnispel]

Due to many service visits I was able to drive different loaner cars with TSI engines (Golf 8, O4, Citygo). I also noticed that fuel consumption is going through the roof pretty easily if your driving style is more of the "agile kind". This driving-style related consumption range is way more narrow if I drive my Diesel.

[SteveTheElder]

I tend to agree. Whilst I have a pretty laid back driving style even on country roads (A, B, and C roads) consumption is notably higher than at near steady speed cruising on motorways and trunk roads.

 

I guess that points to the efficiency gains of the variable vane turbos and cylinder deactivation technologies.

[J.R.]

11 hours ago, avi4tor said:

I checked the rev/speed on my 1.5 manual combi this afternoon, and in 6th gear doing 50mph (checked against a gps receiver) the engine was doing 1500 rpm.  So 60mph would be 1800 rpm.

 

Thats quite amazing, taller gearing than many modern diesels, most of the vehicles of my youth had 3.9:1 or higher final drive ratios, 1:1 top gear and 165/13 tyres or worse, 5000rpm at 80mph was very common, to do 20mph/1K RPM was the domain of very powerful executive cruisers I dont think even the Tincorner 1600E with its 3.77:1 final drive managed 20mph/1K RPM.

Edited 27 July, 2023 by J.R.

[Gerrycan]

On 27/07/2023 at 06:49, avi4tor said:

I checked the rev/speed on my 1.5 manual combi this afternoon, and in 6th gear doing 50mph (checked against a gps receiver) the engine was doing 1500 rpm.  So 60mph would be 1800 rpm.

So 70mph would be 2100 rpm (give or take) which is substantially lower than my 1.4tsi calculated 2700 rpm and the reason for the mk4 requirement for more gear changes.

My 6th may well be closer to your 4th gear in gearing. Both engines produce the same 250Nm of torque.

 

A few years back in the UK I had a hire Kia C'eed manual diesel. Fairly average car but it was economical and was delighted to get 60 mpg on tank, however it had very long gearing and the display was always suggesting a lower gear than the engine felt comfortable with. The instantaneous consumption display was a fairly useless bar graph that only showed under 30 mpg. Once I had worked out that the recommendations were wrong and that I could not use 6th below 60 mph, 5th below 50mph, 4th/40mph and so on, my calculated refill consumption improved to 70mpg. It was then a nicer drive and actually able to accelerate more easily. This required more active use of the gearbox was not a biggie, I got a bit more fun AND better consumption.

Edited 28 July, 2023 by Gerrycan

[GWoodhouse]

On 26/07/2023 at 12:13, SteveTheElder said:

@Gerrycan The cylinder deactivation in the 1.5 must contribute something towards that improvement but how much I wouldn't have a clue! I have seen the deactivation cut in at 1300rpm pottering around town in Normal Mode, not aware of it being more active in Eco though logically it would be - I'm now intrigued so will have to check it out.

I was wondering the same thing, I leave mine in Normal mode as I assume the difference at motorway speeds is negligible / nothing. Always assumed Eco mode was to try and be more economical around town.

[Gerrycan]

10 hours ago, GWoodhouse said:

I was wondering the same thing, I leave mine in Normal mode as I assume the difference at motorway speeds is negligible / nothing. Always assumed Eco mode was to try and be more economical around town.

Let's be clear I have no experience with an engine with cylinder deactivation so I am going by previous owner comments on Briskoda.  I have no real idea how modes affect operation in different driving environments. I don't even have modes on my car but I do have different 'moods' and that can affect consumption

 

The 1.4tsi that was put in the Superb had it and owners reported similar consumption to the lighter/smaller Octavia without it so I assumed it was worth a bit more than 5% improvement.

I do remember reading an early 1.5tsi Octavia owner complaint that the cylinder deactivation did not cut in as much as he expected but it turned out he was trying to lug the engine in similar gears to his previous 1.4tsi and needed to adjust to allow the engine to rev a little more which reduced the load and allowed the cutout to activate, which for his version was reported from 1500 rpm.

I'd love to get my hands on one to see what I could achieve but alas there is no 1.5tsi Aussie Octavia mk4  and I let the purchase opportunity for a really well priced new manual 1.5tsi engine Scala slip by during the instability of the Covid era. The only current one on the market is an interstate demo (2500km away) and about A$20k more expensive than the original including A$8k of packs I don't want.

Edited 28 July, 2023 by Gerrycan

[AlanOsborne]

Hi, my 2020 MkIV 1.5TSI manages between 50 and 60 mpg driving locally and between 64 and 68 mpg on a longer Motorway run (Mainly at 70 mph)  I am using Sainsbury's Super Unleaded, what do you people use please?  Cheers, Alan

[SteveTheElder]

15 hours ago, AlanOsborne said:

Hi, my 2020 MkIV 1.5TSI manages between 50 and 60 mpg driving locally and between 64 and 68 mpg on a longer Motorway run (Mainly at 70 mph)  I am using Sainsbury's Super Unleaded, what do you people use please?  Cheers, Alan

That's better mpg than I'm getting on the motorway trips, mine is usually 60 - 64mpg and locally it'd be low-mid 50s (unless it's in town then in to the 40s.

I usually get the standard Shell E10. Tried V-Power E5 for a consecutive few tankfuls, near as no matter the same economy but it felt a bit smoother.

Is the Sainsbury's Super Unleaded E10 or E5?

Does your 1.5 have mode selection? If so, which mode do you normally use?

[AlanOsborne]

Hi, my 1.5 is the SE Technology, therefore no mode selection.  Sainsbury's Super Unleaded is E5 (Or less) and I attempt to drive with a light right foot, quite often on two cylinders at 70 mph.

 

I was told by a Skoda Technician that the 1.5 TSI engine should run more smoothly and efficiently on fuels with >95 RON - Indeed the manual says 'Using higher octane petrol than 95 RON may result in improved performance and lower fuel consumption.'   It's all a bit of a grey area and very subjective isn't it?  But I reason that Sainsbury's SUL is cheaper than some branded 95 RON fuels, therefore why not -  As you say, the car 'Feels' smoother on a higher Octane fuel, even so, there is not a great difference between your observations and mine

[Ootohere]

[GWoodhouse]

18 hours ago, AlanOsborne said:

Hi, my 2020 MkIV 1.5TSI manages between 50 and 60 mpg driving locally and between 64 and 68 mpg on a longer Motorway run (Mainly at 70 mph)  I am using Sainsbury's Super Unleaded, what do you people use please?  Cheers, Alan

That's seriously impressive 🤯 What does that equate to out of a tank? I thought I drove economically but clearly not! My 56mpg was mainly but not exclusively motorway / A roads.

 

Might start experimenting with some different fuels...

[AlanOsborne]

Hi, we (Wife, me, dog, cat and luggage) recently went on a trip to Kent for a week.  This included the usual M6/ M1/ M25 traffic and local driving in and around Westgate on Sea,  - We accomplished this on one tank of petrol and covered 588 miles in total.   I have seen over 650 miles on occasion (very favourable driving conditions)  However, I no longer have to commute and can therefore avoid most traffic jams and bottlenecks.  I also live near Wrexham and have good access to dual carriageways etc. 

 

[SouthernComfort]

Again, no opportunity to comment on the 1.5tsi in our market, but FWIW, having covered less than 2000km from new in my 1.4tsi 8 speed auto I have no complaints about fuel economy. Short distance suburban running returns around 7l/100km (40.5 mpg). Average highway/freeway driving averages 4.8l/100km (58.8mpg) although I have experienced as low as 4.5l/100km (62.7 mpg) depending on distance and constancy of speed etc. The 8sp is smooth with plenty of torque and compares favourably in every way with the Golf mk7 1.4tsi 7sp DSG that I had a few years back. Personally speaking, I don't see the benefit of 1.8 or 2.0 engines given the performance this 1.4 puts out. 

 

Having lately been used to a V6 CRD Jeep Grand Cherokee 4x4 (frequently pulling an off-road caravan), I don't even think about the Skoda's consumption day to day, it's pure joy!

[Felix2021]

On 26/07/2023 at 05:31, Gerrycan said:

1.5tsi with variable geometry turbo

That is only available in 130HP version. 150HP is using standard turbo.

I believe 150HP version will get variable turbo in EVO2 version, which starts being marketed now, but not available in O4. Will probably be after facelift.

On 26/07/2023 at 05:31, Gerrycan said:

2.0tsi 'Budack' cycle engine is still in the Skoda range and if it actually was more efficient

I THINK, that all 190HP versions are Budack cycle now.

Yes, it's more efficient than "normal" 2.0, but greatly depends on driving style.

Friend of mine has A4 with this engine. Driving around Finland (huge fines for overspeeding) he's getting avarage consumption of 5,5 l/100km. Impressive result, but mostly due to driving style.

On 26/07/2023 at 05:31, Gerrycan said:

whether there is a 2.0tsi with cylinder deactivation

No.

On 26/07/2023 at 06:23, avi4tor said:

 I used to have a 1.8, and it was more flexible and an easier drive.  With the 1.8 I would do most driving in 5th and 6th gears, with the 1.5 I have to drop to 4th much too frequently.

As noted already by someone, it's more about gear ratios than engine as such.

1.5 is much more efficient than 1.8, and suitable for most users i would say. I very rarely use all it's power.

When you think about gearbox however, you are right. Seems that they have overdone it with ratios. Sacrifising driving experience over (on paper) efficiency.