90tsi vs 77tdi

[aerohydro]

While probably pretty few people have experience with both of the bottom end versions, I'd like to hear some opinions. The 77tdi is short a few kW and a gear (I'm assuming manual here), but does it make up for this with better torque? I've done a rough calculation of fuel cost, and the diesel costs about $380 less per year assuming 15000km. What about servicing costs? What else is there to think about? One point is that there are much fewer of the 77tdi's out there judging by carsales listings.

What do people think?

[Ryan_R]

Lower powered petrol Golfs have the 7 speed DSG, vs the 6 speed DSG in the sporty and diesel variants. For Manual Transmission they'd both be 6spd.

Best to take both for a test drive to compare them. Diesel usually costs a bit more to start off with, might have higher servicing costs down the track, and fuel savings depends on what sort of trips you make.

[Jake02]

The 77TDI only makes sense to me as a GreenLine and since Skoda Aus doesn't import the GreenLine, leave it... 90TSI for the win, and the 118TSI isn't much more than the 77TDI (yet comes with a lot more equipment) so I'd look at that too.

[Transporter]

The servicing costs should be lower in TDI due to the spark plugs in TSI, both variants use the same engine oil.

[BluChris]

Probably comes down to how and where you drive. I used to do a lot of freeway/flat road steady speed driving and the diesel loved this. Now do lots of hills and stop start, less diesel love for this and if this were my drive when I bought I'd probably have gone petrol.

[cbay]

Not sure if this helps but my own experience is on weekdays I do around 3 hours of stop-start peak hour driving with spirited spurts now and then, and my 90TSI wagon is fine with it so far. I'm getting around 8.5L/100km, a bit higher than the advertised 'urban' figure of 8.2.

I've cut down to at least 2/3 of my previous car's fuel bill, so I'm pretty happy.

[Mysticality]

The 77TDI has a 5spd manual box.

[brad]

The servicing costs should be lower in TDI due to the spark plugs in TSI, both variants use the same engine oil.

Spark plugs are every 90,000km (they are on my 118tsi)<$30 each plus 15mins each R&R (max)? So an extra $230 every 90,000km. Is 90TSI belt or chain?

[Transporter]

Spark plugs are every 90,000km (they are on my 118tsi)<$30 each plus 15mins each R&R (max)? So an extra $230 every 90,000km. Is 90TSI belt or chain?

The 90 TSI is a chain engine, if you didn't know and just asking.

Many new car buyers wouldn't own the 77TDI in the time when it would need relacing timing belt, but if they would, by then, you would be replacing the spark plugs in TSI at least second time and who knows how many igition coils.

However, if you keep your car for many years and hundreds of thousands of km's, then just hope that the timing chain in TSI last that long. Because, I wouldn't want to pay the bill.

[brad]

nope, didn't know, hence the question mark.

If a new car buyer didn't own a 77tdi in the belt change period (what is it - 200,000km for them now?) then it's probably unlikely they'd own it for the 90,000km period that the spark plugs stay in for (eg: if your on a lease then you probably turn-over at 3-4 years).

Oddly, it appears that a lot of new Skoda buyers (esp the budget models) are hoping to be in it for the long haul with 10+ year ownership plans. Certainly that's how I entered into the deal - if the car proved itself during the 2 year lease period then I'd buy it & keep it. At this point, I can see me driving it for another 2.5 years (which will be a piddling 140,000km by then) and then gifting it to my daughter to drive while she does Uni for 4 years & buying another new car to keep for 6 years.

Coil packs? 90,000km & no issues. Sure to happen before the next spark plug change though.

The more I do the sums, the more I think there isn't a huge long term difference in maintenance costs between diesel & petrol models (it might be $100pa in favour of the diesel).

[kaanage]

Factor in a likely DPF replacement (~A$4000?) for the TDi every 100,000km for mostly suburban/city users if the implementation is anything like that of the 6R Polo. With the heavier body, the Octavia will generate more soot so it could even be worse.

[brad]

Factor in a likely DPF replacement (~A$4000?) for the TDi every 100,000km for mostly suburban/city users if the implementation is anything like that of the 6R Polo. With the heavier body, the Octavia will generate more soot so it could even be worse.

I guess if you factored in worst case scenario for both fuel types it would still come out pretty even........ except if you factored in worst case you'd probably stick with walking & public transport.

[Transporter]

Factor in a likely DPF replacement (~A$4000?) for the TDi every 100,000km for mostly suburban/city users if the implementation is anything like that of the 6R Polo. With the heavier body, the Octavia will generate more soot so it could even be worse.

Let’s just not run the scare mongering campaign about the cars with the DPF. No engine is faultless and to be honest, the TSI engines have their own fair share of problems.

But, please don’t see me as the TSI basher, we have RS Octy TSI in family too, and I love that engine for its torque, general performance and still good fuel economy. I made my comment only because of the other comment about the servicing costs. I still believe that, if one keeps the car for up to 160,000km/10 years then the TDI would cost less to run.

But, you’re right, if the bad luck strikes and one buys contaminated fuel somewhere, then the TDI could be in much more troubles than the TSI.

The DPF is good for more than 160,000km when it gets checked for the particles loading. Our 4 years old Touareg V6TDI is driven only in the city now and I don't see any increase in particles in the DPF, the same goes for Tiguan - almost 2 years, done 12,000km of short trips only and the DPF is as clean as the whistle.

[kaanage]

If you look at how the 77TDi Polo 6R has fared overseas in city driving (continual DPF regens with early replacements needed in many cases), you will understand my pessimism for the same engine in an even heavier car.

[Mysticality]

But, you’re right, if the bad luck strikes and one buys contaminated fuel somewhere, then the TDI could be in much more troubles than the TSI.

United petrol stations have dodgy diesel.
Avoid at all costs.

Source: Myself; two separate incidents at two separate servo's 100km apart.
I think it was K1W1, who had the friend with an A4 who experienced v.dodgy running and economy after using United diesel.