Mazda 6 Forums banner

1 - 14 of 14 Posts

·
Registered
Joined
·
13 Posts
Discussion Starter #1
Hello Guys,

Could somebody tell me if this garage is sprouting garbage?

Background: -
After driving from my house unhindered (65-70mph) on the M62, M1, A1(M) and then A66 (i think) on my way to Centre Parks Whinfell (CPW) in December the DPF light came on about 1 mile from CPW along with the limp mode light. 4 days later i drive home using the same route again doing a constant 65 -> 70 the whole way home neither the limp mode or DPF light went out.

I took it to one garage who said it would not force regen and would need a new DPF filter. (I always take my cars here and trust them)


The garbage?
I took it back where I purchased it from (less than 6 months ago - 2nd hand) and said it needed a new DPF filter - after many letters they took it to another garage who they claimed the forced regen worked, when i spoke with the garage themselves they said they had to use some foam but it's now spotless. Because of the legal ramifications I asked how could the light have come on at the end of the journey when it should have been in regen mode for nearly all of it.

He said - "The car can pass the point it can regen itself before the dpf warning light has even come on"

I just can't see how that would be true, surely the whole point of the light is to warn you to do 2-3 junctions on the motorway to clear it and not a "too late, you're screwed now"

I'm also concerned as to why it immediately went into limp mode.

The only point of reference I have is my wife's diesel (56 Renault Megane) that (until december) only does short 5-6 mile trips. When the light comes on, there is no limp mode and 2-3 junctions later the DPF is cleared again.
 

·
Registered
Joined
·
13 Posts
Discussion Starter #2
After further discussions with the place where i bought the car and they've told me this......

The DPF will only regen when the car want to, it won't always happen when your travelling at 70mph even for long distances, the issue was caused because the when the light came on you stopped the car and didn't allow it to regen. Then the trip back was too late for it, as it now had a failed regen.

My BS detector is going through the roof.

With that logic, you could have a cleanish DPF, drive 3-4 hours from Leeds to the middle of London, if the light comes on you'll then need to fight your way back out of London onto a motorway for it to clear to then fight your way back in again. If you park up in London instead you're screwed.
 

·
Registered
Joined
·
941 Posts
Just ask all the long haul truckers in North America how much they love that poor stop gap called DPF. Transport trucks go down like that, imagine that nightmare.


I don't have anything useful other than we have seen the peak if diesel in cars and I give it 10 years before no new diesel cars are even available.
 

·
Registered
Joined
·
585 Posts
After further discussions with the place where i bought the car and they've told me this......

The DPF will only regen when the car want to, it won't always happen when your travelling at 70mph even for long distances, the issue was caused because the when the light came on you stopped the car and didn't allow it to regen. Then the trip back was too late for it, as it now had a failed regen.



.
This is somehow alarming for me as I have the diesel variant. I've read some complaints from an Australian article regarding DPF. The solution is to drive it the way you described it.

I just hope that the current design of DPF is better.
 

·
Registered
Joined
·
13 Posts
Discussion Starter #5
It just seems to illogical to design a system that has the potential to force the driver to drive even further.

UK Example.
The drive from Leeds to Newquay is around 6 hours not allowing for your breaks every 2 hours and traffic delays on the "A" roads. The last 2 hours of the trip is on "A" roads as there are no motorways anywhere near Newquay and the "A" roads there swap between 1 and 2 lanes and can be quite congested, especially in the summer months.

So worse case scenario is, you drive for 6 hours (not allowing for stops/traffic) the light comes on, you then need to drive 2 hours back to the motorway (traffic allowing) - go up the motorway, turn round and come back again. Your 6 hour trip is now over 10 - 11 hours with light traffic. It doesn't make sense to me........
 

·
Registered
Joined
·
585 Posts
What I've read is that if you frequently drive for long hours, you won't have a problem with DPF. I think that is for newer version so you don't have to worry about regen. My friend told me about this however, I haven't read any article about it.
 

·
Registered
Joined
·
13 Posts
Discussion Starter #7
I'll try staying away from Supermarket Diesel - I've just filled up with Shell V-Power Diesel to see if that helps keep the DPF horrors away. There is also DPF cleaner additives you can get, but i think this is part of Premium Diesel fuel anyways.
 

·
Registered
Joined
·
13 Posts
Discussion Starter #9
I contacted Mazda UK (as suggested by the garage) about what happened on the trip too and from Whinfell and this is the response - uneditted.

Thank you for getting in touch using our Contact us Page.



After consulting with the Technical Support Team here at Head Office they have confirmed based on your enquiry it sounds like there is an issue with the vehicle, as it should regenerate easily at motorway speeds, so we would recommend the vehicle is taken to a Mazda dealer for diagnosis.



If there is anything else I can do please do get back in touch.


As I see it, the car should as I have suspected regenned itself and not as the garage is telling me.
 

·
Registered
Joined
·
2,657 Posts
DPFs are a pain in the butt. They're WEAR ITEMS and yes, this means they wear OUT. In passenger vehicles they combine the DPF with the cat, so when it wears out (not if!) you get to buy a new cat that's not broken -- and spend 2-3x as much money as necessary. Oh, and the combined design means you can't clean them mechanically off-vehicle either.

Heavy trucks have the DPF and cat separate. Yeah.

I will not buy a vehicle with one, which means no newer diesel for me -- and this is one of the (many) reasons. DEF is another expensive nightmare when something goes wrong with the urea injection system.

Normally it will regen on its own when on the highway, but if it's failing to do so and you are putting a reasonable amount of highway drive-time on the vehicle the DPF has probably failed, and you won't like the price of having it replaced.
 

·
Registered
Joined
·
585 Posts
DPFs are a pain in the butt. They're WEAR ITEMS and yes, this means they wear OUT. In passenger vehicles they combine the DPF with the cat, so when it wears out (not if!) you get to buy a new cat that's not broken -- and spend 2-3x as much money as necessary. Oh, and the combined design means you can't clean them mechanically off-vehicle either.

Heavy trucks have the DPF and cat separate. Yeah.

I will not buy a vehicle with one, which means no newer diesel for me -- and this is one of the (many) reasons. DEF is another expensive nightmare when something goes wrong with the urea injection system.

Normally it will regen on its own when on the highway, but if it's failing to do so and you are putting a reasonable amount of highway drive-time on the vehicle the DPF has probably failed, and you won't like the price of having it replaced.
Wear out items? Then that means that I'll have the "delete" option. I hope I have the extra money for the modification of the exhaust when the time comes, and also hoping that an update for OVT is free.


If I may ask, what is DEF?
 

·
Registered
Joined
·
2,657 Posts
DEF = Diesel Exhaust Fluid. It's urea, basically, and many newer diesels use it as an aftertreatment to further reduce pollution. Run out and your car won't start (yes, you must add it.) Modern OTR truck engines use it too (and there actually PUMPS for it at truck stops now, as well as being sold in multi-gallon "carboy" style containers.)

The delete option only works if you don't live somewhere that demands emission testing on diesels and can/will catch it. If you do, then no soup (registration renewal) for you.
 

·
Registered
Joined
·
585 Posts
DEF = Diesel Exhaust Fluid. It's urea, basically, and many newer diesels use it as an aftertreatment to further reduce pollution. Run out and your car won't start (yes, you must add it.) Modern OTR truck engines use it too (and there actually PUMPS for it at truck stops now, as well as being sold in multi-gallon "carboy" style containers.)

The delete option only works if you don't live somewhere that demands emission testing on diesels and can/will catch it. If you do, then no soup (registration renewal) for you.
I don't think my Mazda 6 diesel has this one. I don't have a separate tank for filling this thing up. I asked the dealer where is this DPF and that's it. I mean, the guy didn't mention about this DEF. I'm running 30,000 km right now and I just visited our dealer yesterday for my free oil and oil filter including labor. Since it is free, I asked the tech guys to have a lunch with me in a nearby cheap buffet restaurant.

I've encountered this DEF with a colleague who owns a Volkswagen golf. It has a separate tank and you are correct about the engine stopping once you depleted the fluid.

Regarding the delete option, I really hope I don't have to do that.

If I may request, can you instead reply directly to my post? I want to follow your reply and I want to be notified immediately on my email if ever you are answering directly to my post. I find this important coming from a guy who's running with hundreds of thousands of kilometers with the 6.
 
1 - 14 of 14 Posts
About this Discussion
13 Replies
4 Participants
Archerfish
Mazda 6 Forums
Mazda6club.com is a forum dedicated to the Mazda6 / Atenza. Come and discuss reliability, performance, modifications, and more!
Full Forum Listing
Top