Hi,

 

A few years ago I changed from my 2009 diesel Octavia to a 2017 petrol superb, one factor was how noisy the diesel was.

 

Am considering going back to an Octavia as the boot on the non phev is nearly as big as the superb but running costs will be better.

 

I'd be grateful to know how noisy/quiet  the newer diesels are compared to the petrols? 

 

Thanks,

 

Mark

2 hours ago, mark674500 said:

Hi,

 

A few years ago I changed from my 2009 diesel Octavia to a 2017 petrol superb, one factor was how noisy the diesel was.

 

Am considering going back to an Octavia as the boot on the non phev is nearly as big as the superb but running costs will be better.

 

I'd be grateful to know how noisy/quiet  the newer diesels are compared to the petrols? 

 

Thanks,

 

Mark

Hi

Admitting if you are stud at the side of cars on tick over  you would  be able to tell the difference, but when you are in the car driving you won't tell any difference.

I much prefer a diesel    

It depends on the age of the engine - if you are keeping the car for a long while then the diesel will 'age' quicker than the petrol.  I did once try a diesel (Peugeot 405 GLDT) which I kept from new for over 100,000 miles, and after awhile whenever I engaged the turbo (aka a heavy right foot) I got a plume of oily smoke from the exhaust.  I decided the pros of a diesel weren't worth it.

I dont think that is true, a 500000 mile diesel will in general sound no more knocky than a 200000 mile one, I have yet to experience a petrol engine at half that mileage that still sounds sweet, most are scrapped before they get that far, they have remarkable longevity compared to pre 90's petrol and diesel engines but its still the diesels that rack up the huge mileages.

 

One of the reasons is that the cylinder blocks, crankshafts, connecting rods, pistons etc are much more robust to cope with the higher compression ratio and combustion pressure, the common factor for modern engine longevity of both fuel types is detergent fuels, modern synthetic or synthetic based oils, better machining processes and ECU control of fuelling and ignition advance.

2 hours ago, J.R. said:

I dont think that is true, a 500000 mile diesel will in general sound no more knocky than a 200000 mile one, I have yet to experience a petrol engine at half that mileage that still sounds sweet, most are scrapped before they get that far, they have remarkable longevity compared to pre 90's petrol and diesel engines but its still the diesels that rack up the huge mileages.

 

One of the reasons is that the cylinder blocks, crankshafts, connecting rods, pistons etc are much more robust to cope with the higher compression ratio and combustion pressure, the common factor for modern engine longevity of both fuel types is detergent fuels, modern synthetic or synthetic based oils, better machining processes and ECU control of fuelling and ignition advance.

Have you any views on the sound levels?

Sorry no.  I have poor hearing, they are just cars to me & a TDI can sound quite sporty. 

 

Interested in lower running costs of the TDI with SCR rather than a TSI.

 

?

How many miles a day or week do you do and are these outwith the London area? 

10 minutes ago, Rooted said:

Sorry no.  I have poor hearing, they are just cars to me & a TDI can sound quite sporty. 

 

Interested in lower running costs of the TDI with SCR rather than a TSI.

 

?

How many miles a day or week do you do and are these outwith the London area? 

Live in London, WFH , odd drive to Midlands. 

Mine is fine, and tbh I dont really notice the engine noise, it definately is not like the old diesels. When driving you cant really tell the difference as other noises are louder. Unless you particularly dislike a diesel engine noise, i would not worry about it. 

The only time I notice it is when the gearbox holds the revs when cold too long but thats just because it goes a bit mad occaisionaly, not a real issue. When stopped the engine shuts down so no noise.

8 hours ago, mark674500 said:

Have you any views on the sound levels?

Diesels are noisier close up but not so when behind the wheel, different for sure, not sewing machine like as many new petrol engines can be, the best example of that would be the MK1 Polo 900cc engine, but diesels remain muted throughout the rev range (from inside the cabin) and dont sound stressed when under maximum torque like most petrol engines do.

 

But the point in question is your assertion that a diesel engine will "age quicker" than a petrol engine which I strongly disagree with, lets take a couple of extreme examples, the MK1 Polo I mentioned an engine that virtually sings and the PD VW TDi that sounds like a tractor even when new, driven hard through the gears uphill the Polo's singing will get a lot louder and more insistent, more of a screech and like most petrol engines you dont need the rev counter to warn you of over-revving, the PD TDi remains muted from within the cabin and unless the DMF is shot will not sound any thrashier driven in the manner described which would be pointless anyway as you would normally change up at much lower revs.

 

The PD TDi will not sound appreciably different after 500000 miles with regular and correct oil changes, the Polo engine would never get that far and whilst the pleasant singing noise will still be there there will be an accompanying orchestra of mechanical noise from a worn valve train (luckily no timing chain), piston slap and to a lesser degree bearing wear.

13 hours ago, avi4tor said:

It depends on the age of the engine - if you are keeping the car for a long while then the diesel will 'age' quicker than the petrol.  I did once try a diesel (Peugeot 405 GLDT) which I kept from new for over 100,000 miles, and after awhile whenever I engaged the turbo (aka a heavy right foot) I got a plume of oily smoke from the exhaust.  I decided the pros of a diesel weren't worth it.

 

Might I politely suggest that's generalised nonsense.  I owned and drove this for 8 years and 238,00 miles from new until a low speed collision in the city wrote it off.  It was running as sweetly then as when it was new.  It was on the original turbo and the head had never been lifted.  

I thrashed it from the point at which I'd completed running it in.  I towed a very large caravan with it on occasions, spent long periods at 100 mph on the Autoroute, squealed round an open road race circuit in France, commuted in it, drove it off road, etc...

 

Edited 12 February, 20242 yr by Schtum

If you didn't like the diesel before, you are still going to find them noisy if you get another. They have got a bit more refined but at the end of the day there is more noise and vibration from a diesel than a petrol, especially if you are used to a petrol engine which you can barely tell is running most of the time.

 

For most of us that are used to diesels it's not an issue but on the extremely rare occation I get in a modern petrol I can appreciate how quiet it is at standstill. Driving around you will still hear the same road noise whichever way you go as modern cars are very well insulated from the sounds in the engine bay.

On 12/02/2024 at 09:11, avi4tor said:

It depends on the age of the engine - if you are keeping the car for a long while then the diesel will 'age' quicker than the petrol.  I did once try a diesel (Peugeot 405 GLDT) which I kept from new for over 100,000 miles, and after awhile whenever I engaged the turbo (aka a heavy right foot) I got a plume of oily smoke from the exhaust.  I decided the pros of a diesel weren't worth it.

I have to disagree. I have put starship mileage on diesel’s over the years. I currently have a remapped VW diesel 2.0TDI 290bhp from new and now has done 200,000 miles. Runs like new and no oil burning.

 

Going back to the OP a friend recently bought a Tiguan with the 150bhp Evo engine. It’s the quietist diesel engine i have heard to date. I’m sure the 200bhp evo engine is quite similar.

New ones are not as bad noise wise as those from decade ago, but you will definitely hear it on a cold frosty morning.

 

The bigger question is about costs, the emissions equipment added to them to meet euro6d is horrendously expensive to fix if it goes wrong, or starts to clog up.  
 

With many of the diesels now nearer £2k more than petrol equivalent, diesel regularly 15p per litre more, it can take a driver doing under 15k miles per year over a decade to make savings that cover the higher price.  Remember a diesel doing a regen will do about 25mpg, and if that is half an hour once a fortnight  it Is going to change average mpg (regen mpg are excluded from official figures)

 

I had a MK3 1.6 diesel and it was noisy, it was the worst thing about the car. I believe the 2 litre is quieter. Also I have driven a 2 litre Mk4 and it was nowhere near as noisy as my 1.6 MK3. I would say take one for a test drive to see how you find it.

 

The only noise issue I have with my 1.4 hybrid is road noise is higher than I'd like. I think that's always been an issue with Skoda Octavias.

Edited 14 February, 20242 yr by mccririck

6 hours ago, SurreyJohn said:

Remember a diesel doing a regen will do about 25mpg,

 

No way! What makes you believe that?

 

I keep a hawk-like eye on both average and instantaneous fuel consumption and for a very long while on the frequency of and parameters of the then frequent DPF regens before I took action (EGR emulator/simulator and emissions "fix" software rollback, this included live data of EGR temperatures and instantaneous fuel consumption, yes it used enough additional fuel to be measurable but nothing like what you claim unless the vehicle only returned 26mpg normally.

 

I dont like any waste of fuel and always drive economically, I did not like the thought of the extra fuel being wasted on regens that were not needed but of far more concern to me was the possibility of engine oil dilution, bore wear and general engine wear due to degraded oil.

 

I agree with your other sentiments regarding modern diesels especially EU5 and EU6.

Edited 14 February, 20242 yr by J.R.

On 14/02/2024 at 07:17, SurreyJohn said:

Remember a diesel doing a regen will do about 25mpg,

 Something very very wrong with your diesel if you can notice the difference at all between a journey with a regen and without. The amount of diesel a regen consumes is a lot less than the normal variables of driving e.g wind/wet road surface/temperature etc.

It must be true, I read it on a forum! 😁