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I need a new car. A work mate is selling a 14 plate 2L diesel Mondeo with 64k on the clock. Price is £1k lower compared to anything on the internet and they're trustworthy and reliable. It's been well looked after I think.
Question is, it's done between 1 and 3k miles per year for the past 5 years. Mostly short trips. Having read other threads I don't think diesel engines like small trips... Am I buying a well priced car with future issues? What would you do?
As long as it's not a Euro 6 engine I wouldn't worry
Thanks, am overthinking it. It's a good deal from a person I trust, will buy. Cheers.
It'll be fine but go find a big long motorway hill get some heat into it and blast any crap out of it.
I got a 1.9tTD Golf that was 12 years old & had only done 70,000 miles. It had just had a new cambelt so I was happy to take a chance on it- especially as it was going to be a stop gap.
Thanks to working from home I’ve only put 10,000 miles on it in 3 years. My current commute, twice a week, is a 50 mile round trip so it gets a fair run and hasn’t played up.
Having read other threads I don’t think diesel engines like small trips…
It's only because of the dpf systems, in order to work correctly the car needs to get up to temperature and have time to do a dpf regen. So long as it's had a drive more than a few miles/minutes regularly and been able to perform a dpf regen, it'll be fine.
We not long ago Oct 22 bought a 2.0tdci Cmax with 27k on it full ford history one from new on a 66 plate. Again owner used it at around 2-3k a year , weve put 4 k on it since Oct and 4 weeks ago it lit up like a xmas tree gear box malfunction and limp mode. Ford protect and my odb reader both showed EGR blocked . changed under warranty some £850 later at Fords expense..
You are right on the small trips, diesels need a good thrashing every now and again to get them up to temp.
a 66 plate
Which will be a Euro 6 engine. Those are the ones that really struggle with low miles. Earlier diesel engines are much less of an issue
I just got a 2 litre diesel Quashqui (61 plate) with 48,000 miles on the clock. Apart from it being not very economical, it’s a great car. I’d certainly get another.
diesels need a good thrashing every now and again
they don’t. They need to be at operating temperature for a reasonably prolonged time. The DPF won’t regenerate if the engines not warm. But it will also abandon a regen if it’s under high load or high revs.
The Italian tune up thing is an old wives tale. The system is configured to operate under normal driving conditions - so just drive normally.
the thing that would have made a world of difference for euro 5 and 6 engines…… a polite little light on the dash the tells you the DPF is currently doing it’s thing as it’s supposed to - then there wouldn’t be this odd mythology about right and wrong ways to drive.
maccruiskeen+1 Mine is 40mph (definite) for 20-30 mins (I can't remember exactly)
...and been able to perform a dpf regen, it’ll be fine.
That would be my opinion as the owner of a low (6k pa) mileage Euro 6 diesel
Any decent garage will be able to plug in and tell you how full the DPF is in %. A decent service history and you're on the right track
It’ll be fine but go find a big long motorway hill get some heat into it and blast any crap out of it.
The lungs of everyone who lives downwind thank you.
It's interesting how dumping carcinogens into the environment in the interest of convenience is socially acceptable.
Blame the DPF myth, that they make diesel engine clean. They don't, what they do is stop them belching out soot and crap in urban areas. It's all collected then dumped out on motorways and fast country roads instead. It may not come out visible due to the high temps at the time but the crap still comes out.
It’s all collected then dumped out on motorways and fast country roads instead
I don't think so. It's small particles of soot that are collected, instead of being breathed in, and they are then on the main roads they are combusted into CO2 and a tiny bit of ash which remains in the filter.
A DPF regen is not like emptying a hoover bag. It incinerates the soot.
Look up the specific year and model of car to see if it has a DPF. My 2014 van is Euro5 and has a DPF, just ruling out Euro6 doesn't mean you'll avoid it.
(No issues with my DPF except when I used it for a couple of weeks doing very short daily trips when it warned me I'd interrupted it several times)
The lungs of everyone who lives downwind thank you
Aren’t you a pilot?
"a polite little light on the dash the tells you the DPF is currently doing it’s thing as it’s supposed to"
is exactly what trucks and buses have.
if the dpf needs a regen, a good steady cruise on the motorway will suffice.
Different manufacturers will vary, but I know for my diesel subaru it needs to be above 50mph continuously for 20 minutes to start a regen.
which is handy for me, it’s 30 miles to work, along a motorway where maintaining 50+ is rarely a problem.
My car has 125k miles on it and the dpf has never been touched.
my mate has another diesel subaru, same age, and has had to do *something* to his dpf, he does a much shorter commute than I do.
*can’t remember if it was a cleanout or replacement *
and blast any crap out of it.
crap dioesnt get blasted out in a regen any more than during any other driving.
diesel exhaust contains particulates, the dpf filters them out. During a regen a filter doesn’t stop being a filter. The oarticulates are mostly soot and some ash. The soot is incompletely burnt fuel. It is itself flammable. A regen heats the filter and burns off the soot and it exits as ‘not partulates’ because the filter is still a filter and particulates wouldn’t get through. The ash isn’t flammable and stays in the filter and over time accumulates so there is a point eventually (after 100,000 of miles or so) where it’s full and needs changing.
if you’re revving the nuts off the thing or doing a forced regen and seeing plumes or smoke you’re not clearing out the filter - you’re blowing out vaporised fuel from a failed regen
Aren’t you a pilot?
Yep, but that has nothing to do with it. Do you think I build the plane / fuel it / pick the route / randomly fly it around for fun? No. While it's my job it doesn't mean that I can't do it as economically as possible, even though it increases my workload.
Going for a blast to empty the shit out of the exhaust is little different from taking a dump in your local river or throwing your McDonalds litter out of the window.
The lungs of everyone who lives downwind thank you.
It’s interesting how dumping carcinogens into the environment in the interest of convenience is socially acceptable
Tell the OP to buy a petrol then. Shit is going to come out of a diesel exhaust either way.
Shit is going to come out of a diesel exhaust either way.
Not necessarily any more than a petrol.
Going for a blast to empty the shit out of the exhaust is little different from taking a dump in your local river or throwing your McDonalds litter out of the window.
there is an absolutely key difference- and that’s that people are only imagining that they are emptying shit out of there exhaust.
Nothing comes out that wouldn’t come out anyway under normal driving conditions and none of the filtered particlate material, that pre euro 5/6 engines emit all the time, comes out ever.
By ‘going for a blast’ it’s a double delusion because the DPF won’t regenerate anyway. So no there’s both no crap coming out the exhaust and the filter isn’t getting cleaner either.
He's right. Diesel particulates happen when the fuel doesn't fully burn. All that happens when it regenerates is it burns what didn't burn in the first place.
And the VGT vanes? My MK4 PD Golf clogged them if I trundled around in it, the OP's car has done low miles hence take it for a good heat cycle/full boost run
(hides and waits more flaming)
I think the 'going for a blast' predates all our euro 4/5/6 engines.
I used to be told to do this on the old transit MK3, VW T3's VW LT's and LDV diesels which two employers had. They often didn't get too warm or loaded as we 'pottered' with kids on board really. If we ever got a longer trip without guests on board, we were told to clear out injectors etc with a good thrash. One of the centre handymen also had injector cleaner stuff he would pop in the fuel before a longer trip. It did seem to work on those old diesels. 🤷
And the VGT vanes?
That's a bit different to DPFs. They can get oily crud in, and higher speed driving can burn that off but probably just normal A road or motorway. Higher temperatures can remove deposits from valves and other parts to an extent according to some videos I watched but it's a different issue again. I'm not sure about EGR because the valve doesn't stay hot, in fact the gasses are cooled before they go through it (at least on my Passat the valve was on the cold side) so fast driving can't realy burn that off. But having a fully warmed up engine would probably reduce soot so how gunked up your EGR is is probably related to what percentage of the miles were done with a cold engine.
Aren’t you a pilot?
🤣
Aren’t you a pilot?
Aren't you an air traveller?
The Italian tune up thing is an old wives tale. The system is configured to operate under normal driving conditions – so just drive normally.
Back in the old days of carburetters and hot cams, it was a thing. Idling round town would foul the spark plugs and a good thrashing would get things running properly. With modern engines, it's not going to make any difference to performance.
If an engine is just taken on short runs and the oil and exhaust never get fully up to temperature, you can get condensation in the oil and exhaust, which turns the oil to mayonnaise and forms carbonic acid in the exhaust. If I bought a low mileage car, I'd check under the oil filler cap for signs of sludge. Even if the oil looked ok, I'd immediately do an oil and filter change and then give it a decent long drive to get it all up to temperature.