[richierich]

Considering buying a second hand Mark 2 i30 on a 2014/2015 plate.

My annual mileage is only about 5,000 miles and most journeys are local and about 5-10 miles.
I assume the petrol engine i30's are more suitable for low mileage and short journeys so can I rule out a diesel altogether? Would short journeys cause damage to a diesel engine over time?

[AlanHo]

For a number of reasons I would chose a petrol car if you are doing lots of short journeys. The DPF on a diesel will not get a chance to rejuvenate and you would have to take the car for a regular blast on a main road or motorway to clear it.

There is lots of info on this forum about the DPF - yo can use "search" for it

However - it matters not whether you have petrol or diesel - most engine wear occurs when the engine is warming up and regular starting from cold and short journeys are a problem with both types of car.

[The Gonz]

Yes, you'll mostly be advised that for such low mileage you get better value out of a petrol variant, but for a 2nd hand car that may not hold up as a valid argument, so have fun and blast around with Diesel. Go first generation and forget the DPF woes.

[richierich]

Thanks.
I currently own a first generation i30 1.4i on a 2009 plate so want to renew with a second generation i30, on a 2014/15 plate ...

[AlanHo]

If you are happy with the present engine - that might help your decision.

Also - used car prices are already falling and this will only accelerate as the antipathy towards diesels increases. Petrol is the cleaner, and soon to be more popular, option.

[Zag]

Hi, I've used petrol diesel and lpg.

To be honest if you want the cheapest fuel economy go a diesel, they only use a tiny squirt of diesel. So a tank will probably last you 3 or 4 months maybe longer, so you doing 5000 miles around 6000 klms depending on tank size and what the diesel uses might only be 6 to 12 fills for the year.

The diesel I had didn't have the ash burning thing waste of time really as it's ask not co2, but diesels have the lowest co2 output anyway. diesel 4wds can easily beat eco petrol cars in co2 output for the year, you'd be shocked at how bad eco petrol cars are compared to diesel.

That's why I don't understand why vw have been done for emissions when diesel already blows the doors of petrol motors easy, unless it was to make people think electric cars are cleaner. Batteries only last 3 to 5 years with current tech.

I would say check out on here for diesel range but when I look up specs it's a 50ltr diesel tank diesel motor uses around 4 to5ltrs for 100 klm so roughly a range of 1000+ klm a tank, really I'd probably expect say 800 or 900 klm maybe.

In petrol you'll easily be looking at 7 to 9ltr per 100 klm, so 400 to 600 klm a tank.

I'm not sure what that'll be in miles but I'm sure you can see the difference straight away.

Diesel I found were great for getting a set range for set amount of diesel, if the motor used 4 ltr then that's it doesn't matter how fast or slow you go, something i do miss abut diesel.

Also main thing is diesel no coil, leads or sparkplugs, so that cost and problem is gone straight up.

The real important things heater coils, injectors and fuel pump, these are the 3 things that will need to be replaced at some point, they do last a long time though but cost a lot to replace when or even if you need to replace them.

If you want fuel economy then go a diesel it'll beat any petrol motor.

[richierich]

Thanks Zag.

It's not so much about fuel economy. It's wether the DPF's in the dieael will block up with only travelling short distances.
But if a longer run of say 10 miles at 50-60 mph, once a week, would clear the DPF's I wouldn't hesitate in buying a diesel.

[Dazzler]

Thanks Zag.

It's not so much about fuel economy. It's wether the DPF's in the dieael will block up with only travelling short distances.
But if a longer run of say 10 miles at 50-60 mph, once a week, would clear the DPF's I wouldn't hesitate in buying a diesel.

Zag is in OZ where we have only recently got the DPF added to Diesel motor (in the series 3 - PD models) As Alan has explained it really does change things for low mileage drivers. In your case it does appear Petrol would be the better option.

Diesel's superior torque is nice but not worth the hassle for a low mileage driver.

[eye30]

Go for petrol as the newer diesels require, i believe, a good run to keep the dpf clear. 

[AlanHo]

The problem with trying to clear a DPF with a fast run is that it only works when the ECU wants it to.

If the exhaust gas pressure drop across the DPF has not reached the activation setting - a fast run will only add to the soot build up and not burn it off.

When running normally - even at high speed - the exhaust gas temperature is not high enough to burn off the soot. This can only be done when the ECU senses that the DPF is becoming blocked and causes extra fuel to be injected towards the end of the firing stroke - which then burns in the DPF and raises its temperature beyond about 750C.

[andsome]

Why not consider steam? 

[richierich]

Muppet.

[The Gonz]

 

Muppet.