1.5 tsi reliability

[Jazzjames]

We get 50mpg all day long on long trips fully laden with roof box on. 1.5 tsi 130 ST with manual gearbox.

No kangarooing. I’d never drive off until the revs drop to their operating tickover of 800rpm or so, maybe that’s why some people report kangarooing upon cold start.

It isn’t a rocket ship and while it’s night and day between my 1.8 and my wife’s 1.5 in terms of performance, the 1.5 engine’s quiet and smooth, and is fast enough to make good progress. You don’t feel like a liability, which I did in my wife’s old Fiesta.

 

[Glosphil]

Some nonsense being spouted on here about the efficency of 'small' turbo engines.

MY Leon FR 1.4TSi (150) is almost the same weight as the Sierra XR4x4 I once owned but the engine is half the capacity. Same power, slightly faster to 60, more torque at half the revs, 50% higher geared in top & averages 45mpg not 22.

 

[mty12345]

Some nonsense being spouted on here about the efficency of 'small' turbo engines.

MY Leon FR 1.4TSi (150) is almost the same weight as the Sierra XR4x4 I once owned but the engine is half the capacity. Same power, slightly faster to 60, more torque at half the revs, 50% higher geared in top & averages 45mpg not 22.

There is also 40 years of technological development between the two, hardly a fair comparison. I believe the comparison being made was between a 2.0 turbo and a 1.5 turbo. All other things being equal, the BSFC will mean that the 2.0 is more efficient than the 1.5

 

[Jazzjames]

Unscientific 1.8 vs 1.5 fuel economy comparison:

I have a 1.8 tsi 5 door hatch and get about 40mpg long term average from a mix of motorway and city driving. We're in Germany so when I'm on the autobahn, I don't hang about.

My wife has a 1.5 tsi ST (130) and she gets 44mpg as her long term average, mostly city driving. Over 50mpg on a long run is easy to achieve. I'm not sure what's possible with the 1.5 tsi when driving in ideal conditions. With the cylinder deactivation, I guess 60mpg would be possible if you drove really carefully. 50+mpg is also possible with my 1.8 but you have to drive gently. My best mpg on a long run is 55mpg, but that was basically hyper-miling.

When we go on long trips the 1.5 tsi does get better mpg than my 1.8, but it isn't night and day. The ST is heavier but not sure by how much. I think both engines are decent, and whilst I do enjoy the extra go in the 1.8, the 1.5 is fine for transporting baby and dog. I do miss the indy rear suspension, but apart from that the 1.5 is a good engine.

My take: Both engines can be pretty efficient, or pretty thirsty, depending on how you drive. If MPG is super important to you, then learn how to drive more efficiently.

 

[Glosphil]

There is also 40 years of technological development between the two, hardly a fair comparison. I believe the comparison being made was between a 2.0 turbo and a 1.5 turbo. All other things being equal, the BSFC will mean that the 2.0 is more efficient than the 1.5

I was replying to SuperV8.

 

[SuperV8]

Some nonsense being spouted on here about the efficency of 'small' turbo engines.

MY Leon FR 1.4TSi (150) is almost the same weight as the Sierra XR4x4 I once owned but the engine is half the capacity. Same power, slightly faster to 60, more torque at half the revs, 50% higher geared in top & averages 45mpg not 22.

I was replying to SuperV8.

What 'nonsense' of my comment exactly are you referring to??

Not sure comparing the efficiency of a modern 'small' turbo car to a 40 year old Sierra 4x4 with a 2.9l Cologne push rod V6 (engine originating in the 1960's!) is relevant/fair!

Yes, Turbo's are not magic!
They enable smaller capacity engines to flow more air and make more power/torque - BUT at the expense of efficiency. Higher Brake-specific fuel consumption BSFC.
Smaller capacity engines CAN be more efficient but ONLY at lower engine loads.
So the take away - to get good MPG out of modern 'downsized' turbo'd petrol engines try to drive avoiding the turbo and with the ACT try to enable the cylinder de-activation.

 

[Glosphil]

What 'nonsense' of my comment exactly are you referring to??

Not sure comparing the efficiency of a modern 'small' turbo car to a 40 year old Sierra 4x4 with a 2.9l Cologne push rod V6 (engine originating in the 1960's!) is relevant/fair!

I can only compare engines of which I have personal experience.

2005 Honda Civic Type-S 2-litre iVTEC 160hp, torque 132 ftlb at over 4,000rpm. 32mpg. Owned for 7 years.

2018 Leon FR 1.4TSi 150hp 184ftlb at about 2,000rpm & 45mpg. Owned for over 3 years.

The Civic is the newest NA engine I have personal experience of.

Perhaps compare NA version & turbo version of the VAG 1.0 3-cylinder engine? I'll look up the stats.

 

[Tester01]

How would you describe your driving style? I know it's difficult to be subjective - as everyone's opinion of 'gentle' will vary!
What's your typical driving cycle like? miles driven/roads/location?

I would probably do a little test - drive down the motorway (pick a flattish section on a none windy day) re-set your MPG, and set your cruise at 55-60mph (lorry speed!) - and see what your mpg is like over 20 miles?

Definitely agrees everyones opinion will vary.

At the moment during week generally city driving, with a short blast on the dual carriage.

And weekends I like to take a spin down the motorway for a few miles, depending on where I’m going.

My driving style can be a mixed bag from
being heavy footed of to just cruising around.

However I’ve actively been gentle on the accelerator etc for last few weeks and opting more for the sensible and easy going style. Purely trying to see the best economy I can get out of it.


I get it there’s so many factors that can affect fuel consumption.
To me seems somethings up compared to other peoples experiences across the VAG line with this engine.

just cant put finger on it - maybe it needs a major service? Like I said previously the dealer changed the oil, brake fluid and pads afaik before I got it.

And I hate that I’m constantly keeping an eye on MPG.

Will try that motorway test hopefully at the weekend.

Going in again for kangaroo issue, although don’t expect them to be able to fix it. Seemingly as it’s had the update already but see what they say.

Don’t know if I’ll have this much longer shame as I’ve wanted a Seat for like a year now and now look.

 

[Tester01]

Does anyone one know where the MAF sensor plug is located on 1.5 TSI Engines?

Searched online see plenty for Mk1 but not Mk3 Leons.

 

[BigJase88]

Mass Air Flow so it will be after the air filter on the hose coming out of it at the top. Follow the hose from the airbox and you will find it

 

[Tester01]

Mass Air Flow so it will be after the air filter on the hose coming out of it at the top. Follow the hose from the airbox and you will find it

this?

 

[BigJase88]

Dont think so that just looks like a connector?

 

[Tester01]

Dont think so that just looks like a connector?

Yeah thought so odd there’s no connector on the pipe unless I’m completely blind.


when I took the engine cover off noticed this?

guess have another look in daylight tomorrow
Wonder if it only has a MAP and I’m looking for the wrong thing

 

[SuperV8]

Yeah thought so odd there’s no connector on the pipe unless I’m completely blind.


when I took the engine cover off noticed this?

guess have another look in daylight tomorrow
Wonder if it only has a MAP and I’m looking for the wrong thing

If you had a MAF sensor it would be here: so you don't have one.

Looks like you have (at least) 2x air pressure sensors 6 (GX9) & 14 (GX26). They are both combined pressure and temperature sensors so it can calculate the mass of the air from its pressure and temp. If these sensors are showing values outside an expected range I would expect it to flag up a warning light/fault code.
This is the workshop manual for the 1_5 EA211 evo DADA engine:

SeatLeonMK3Manuals – Google Drive

drive.google.com

 

[Tester01]

If you had a MAF sensor it would be here: so you don't have one.
View attachment 34569

Looks like you have (at least) 2x air pressure sensors 6 (GX9) & 14 (GX26). They are both combined pressure and temperature sensors so it can calculate the mass of the air from its pressure and temp. If these sensors are showing values outside an expected range I would expect it to flag up a warning light/fault code.
This is the workshop manual for the 1_5 EA211 evo DADA engine:

SeatLeonMK3Manuals – Google Drive

drive.google.com

View attachment 34570

Was more to try and get to the bottom of my fuel consumption issue, as I saw online sometimes people suggest unplugging your Maf sensor temporarily and seeing how it runs and if theres a noticeable difference in consumption. That might mean it needs a clean.

But looks like you said I dont have one as I did see that induction kit thing.

Not actually checked the values for MAP but do have an obdeleven reader see If I can get some Live data readings, but what would be the expected range?

Looks like my kangaroo issue may be resolved, had an update and dsg adaption done and its no longer noticeably jerking in second.
Whether it'll stay that way and/or its just masked temporarily remains to be seen.

But yeah next goal is to figure why car sips a lot more fuel than others I've spoken to or seen, even on clear motorway trips.
Should've just got a Cupra seeing as Im seeing some with matching or better effiency than me LOL

 

[Tester01]

I might be jinxing this.

Read up online about resetting ECU to reset adaptions for different engine components
By disconnecting battery for a period of time and draining residual power

Went for a 15mile drive and managed to get 38MPG probably.

And managed to get the same yesterday evening.

Highest I’ve got since owning the car last few months so promising.

Considering a lot of the time I struggled to get near 30 majority of the time.

 

[Glosphil]

I regularly do a 15 mile drive from my house to a friend in Cheltenham. Mixture of 40, 50 & 60 limits on a hilly country road. My 2018 Leon FR 1.4TSi DSG never returns less than 47mpg for that journey & occasionally manages over 50. A 155 mile trip to Sheffield, mainly on motorway returns more than 50. I am not a slow driver & have received communication from various police forces in confirmation.

Certainly something wrong with your car.

 

[Tester01]

I regularly do a 15 mile drive from my house to a friend in Cheltenham. Mixture of 40, 50 & 60 limits on a hilly country road. My 2018 Leon FR 1.4TSi DSG never returns less than 47mpg for that journey & occasionally manages over 50. A 155 mile trip to Sheffield, mainly on motorway returns more than 50. I am not a slow driver & have received communication from various police forces in confirmation.

Certainly something wrong with your car.

Don’t disagree at all!
Just getting to the bottom of without spending an arm and a leg.

Especially when I have no fault codes to even suggest where the issue may lie.

Thrown some system cleaner in the meantime.

Just don’t know what else I could look at to help diagnose why

 

[Tester01]

Yeah MPG is still crap thought I was getting somewhere.
Feel like ive hijacked this thread so apologies.

Just dont know what it is, did two 60 mile round trips over the weekend mainly motorway
And still touched about 37MPG following limits.

Know it was cold etc but just annoying and frustrating, what could be causing such a poor reading.

Friend has a an Audi with the same engine and has better economy.
Regret buying it.

Just dont know what to try next

 

[SuperV8]

Yeah MPG is still crap thought I was getting somewhere.
Feel like ive hijacked this thread so apologies.

Just dont know what it is, did two 60 mile round trips over the weekend mainly motorway
And still touched about 37MPG following limits.

Know it was cold etc but just annoying and frustrating, what could be causing such a poor reading.

Friend has a an Audi with the same engine and has better economy.
Regret buying it.

Just dont know what to try next

How are you measuring your MPG?
The trip computer has several variations -
MPG for trip
MPG since fill up
Long term MPG
Instantaneous MPG