DPF (diesel particulate filter) advice

The engine on a modern diesel, should, if looked after correctly last forever, but due to the emmissions laws, and how tech has evolved, normally all the electronics, and exhaust cats, dpf, egr related items fail regular. An old diesel engine is far better for mixed driving, unfortunately its just how the law is now days on emissions sadly

This is true but having said that a lot of manufacturers have refined their petrol engines right down now to get pretty similar MPG figures to the older diesel engines.

Really diesel isn't worth having these days unless you do about 16k+
 
I have owned a car with a DPF.

I will never do so again.

Me too. I now despise all diesels because of this. Although it did mean I replaced it with an impreza. :D So now if I get a huge bill I'm sat in an Impreza and not an awful tractor...

Just to clarify I replaced 3 injectors and a DPF in the two years I owned the car even with a motorway blast twice a day. Still, there's obviously a market for them or they wouldn't exist.
 
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Why you guys moaning about DPF? People who have owned a car with one will be well aware a decent exhaust specialist and remapper can sort all these issues out for you for very little cost. If not (absolute worst situation) get a diagnostics kit for your specific vehicle and manually trigger the dpf regen when your on a motorway
 
Why you guys moaning about DPF? People who have owned a car with one will be well aware a decent exhaust specialist and remapper can sort all these issues out for you for very little cost. If not (absolute worst situation) get a diagnostics kit for your specific vehicle and manually trigger the dpf regen when your on a motorway

Yeah, because everyone knows and cares about things like that. I mean, I bet all of the mums who take their kids to my local school know a good exhaust specialist and remapper.

The first time most people know anything about a DPF is when their car fails it's MoT or starts to drive oddly and the dealer slaps them with a big bill to replace it.
 
Yeah, because everyone knows and cares about things like that. I mean, I bet all of the mums who take their kids to my local school know a good exhaust specialist and remapper.

The first time most people know anything about a DPF is when their car fails it's MoT or starts to drive oddly and the dealer slaps them with a big bill to replace it.


I see your point tbf, I got lucky in the sense of mine doesn't have one but if it did it would have been gone within days of owning it. Diesel is just being ruined tbf i know its all about emissions etc but making a diesel more sluggish isn't going to appeal to no one soon. If they put these things on 1.3cdti's etc who's gona want them? I wouldn't take a 1.3 much further than around town/short dual carriage ways. Stop me if i make no sense but i don't get it sometimes
 
I have a diesel insignia.

If/when the dpf fails, it's £250 at local garage to remove and remap it.

So for tge meantime im enjoying the better mpg, and more torque (160bhp version)
 
I see your point tbf, I got lucky in the sense of mine doesn't have one but if it did it would have been gone within days of owning it. Diesel is just being ruined tbf i know its all about emissions etc but making a diesel more sluggish isn't going to appeal to no one soon. If they put these things on 1.3cdti's etc who's gona want them? I wouldn't take a 1.3 much further than around town/short dual carriage ways. Stop me if i make no sense but i don't get it sometimes

It's all about the mpg and the VED.
People will happily spend thousands of pounds to save £100 on VED. Likewise, they will buy a new car that does 60mpg on the combined cycle for their 5000 mile per year use case.

When I started my career, I remember people in the smoking room talking about 0-60 times, bhp, top speed and equipment. Now all they want to talk about is g/km and mpg.

Suits me though. It means that exotic V8 super saloons depreciate like a fake Van Gogh so I can buy them for a pittance.
 
It's all about the mpg and the VED.
People will happily spend thousands of pounds to save £100 on VED. Likewise, they will buy a new car that does 60mpg on the combined cycle for their 5000 mile per year use case.

When I started my career, I remember people in the smoking room talking about 0-60 times, bhp, top speed and equipment. Now all they want to talk about is g/km and mpg.

Suits me though. It means that exotic V8 super saloons depreciate like a fake Van Gogh so I can buy them for a pittance.

Works out well for some eh. Mine does 60mpg happily but it isn't too nippy but economical was what i was after
 
I've never regretted owning a diesel, had 2 now over 6 years, nether had dpf problems during ownership, one had a EGR valve fail but that wasn't expensive to fix.

Its been done to death here, diesel is right when you do the miles.
 
Same, the the diesel in the XF is excellent (obviously not as good at the SC 5.0 V8) and in the two years I've had it I havent had any DPF problems. Fantastic car and engine that I would happily get another one.
 
Since doing less mileage I have had to force one DPF regen. Did it with a £6 elm lead and some software on the laptop.

Doing it is pretty scary as the engine revs to like 4,000 rpm and sits there revving for about 10 minutes. The heat is incredible, you literally can't stand next to the car. Still it is the only one I have had to do and worked incredibly well.

After that I stopped the missus from doing the ridiculously short school runs. I will say however the dealer price for a new DPF has dropped from around £900 to £352. DPF's are like Cats when they first came out that caused lots of problems. They are getting better and cheaper.
 
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As a whole I've had few issues with the DPF on my E350CDI. When it needs to regenerate, it automatically changes down a gear or two for 10 minutes of so (so at 30MPH it is doing 1,700RPM instead of 1,000RPM) and when complete goes back to normal.

However, I have found if I'm doing a lot of town driving and don't allow the regeneration to complete it will throw the car into limp mode. This has only happened to me twice in two years and I have learnt if it is doing a regeneration, make sure my next drive is at least a few miles to give it chance to complete.
 
Ah yes, equal scare stories about CAT's, I had a sensor fail on a Mondeo and that in turn caused the CAT to be killed, best part of £1k at the time.
 
I know a mechanic who deals with modern diesels and particularly DPF issues. He said to me a while back that he felt an awful lot of dealers were unnecessarily replacing them rather than regenerating them.

He has even cleared them by drilling and tapping a small hole in them to allow the excessive soot to escape during a forced regen. Then simply putting a bolt and sealing washer in place.

Best advice is to shop around if you have problems, I think there is still a lack of understanding in the trade.
 
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