Because it's more expensive.
Driving my diesel to keep the DPF from imploding?
- Thread starter Feek
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Because it's more expensive.
Still want to know what the indie garage in one of the villages near me had in their diesel pump marked "regular" until 2019 as it definitely gave different results if I had a tank full of it vs the one marked B7 - no price difference. A 10% difference in MPG and notably smoother more responsive engine doesn't come down to coincidence (though their B7 seems lower quality than the coop I more usually top up at).
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In many instances ragging a car will cause a DPF regen to terminate. The car is trying to keep exhaust temps high (yet too high damages components), but abusing the engine makes it difficult to keep a stable EGT, so the car eventually gives up to stop cat damage.
Also in my car, engine speeds over 4000 RPM cause automatic pausing of regen, and termination if it happens to much (regardless of load, so holding very high RPM will fail).
The absolute best conditions for regeneration is motorway driving. The limited variation in engine load allows the ECU to keep the temps at the perfect range for the whole regen cycle.
I was actually told by Vauxhall that too much motorway driving WOULD clog the DPF.
Sixth gear at 70mph just didn't get my car hot enough apparently ...
Not all diesels are the same, mines happy don't short journeys, for a diesel anyway.
That's absolute nonsense. 70mph cruise it will easily get up to operating temperature, and will be where it produces the least amount of soot. Then when it needs to regen it's fully capable of getting the DPF hot enough by itself.
It was something to do with "not hot enough / revs to trigger regen"
Personally I thing it was rowlocks to stop me getting them to fix it (car had only done 16K miles from new)
Dunno about Vauxhall but on my vehicles as long as the vehicle is up to normal operating temperatures if it detects a regen needed it will alter the injectors, etc. to get enough heat for a DPF regen - so "too much" motorway driving wouldn't be a problem (I assume this is how they all work). Can be a little unsettling if you don't know what is happening as the difference in engine note, etc. at first would seem like something had gone wrong - though I tend to find I'm more sensitive to that than most people.
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I can assure you that they wouldn't design it to not rehen at cruise speeds. A car with regen at 1200rpm quite happily, rpm has very little to do with the regeneration.
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Stay in 5th then
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That sounds like a sale agent that's fobbing you off. I own a vauxhall too and they no problem completeing a regen under motorway condition. The TSB that was issued to dealers event highlights motorway driving as the 'most favourable condition' for a regen cycle.
My model uses the A20DET engine was runs at about 1750 RPM in sixth at 70 MPH. It's a non ad-blue model so it uses late injection to raise EGTs. If you use OBD tool you can watch the DPF temperatures during regenartion. It holds 600 C like a dream on the motorway. Heck, even if you do 55 in sixth gear the car completes a regen cycle perfectly because it just late injects more to compensate and the constant load allows it to cycle complete. It's telling the first three word used in the TSB answer even say "under constant conditions" and mention nothing about high RPM. Any car throwing DPF related faults during motorway driving has a DPF fault IMHO.
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I have a 2010 2.0l Diesel Focus and we only do about 7k a year and all mostly shopping trips -Up to now I have never seen a DPF light on and don't even know if it has one.
I do the occasional thrash half way to Chester from Whitchurch in low gear and keep revs up around 3k. I can tell it's doing a regen as temp rises and stays there till it's done - just keep driving till temp drops to normal.
Also put bottle of something in fuel tank to help it along last time. Never see any black soot out the exhaust at all.
I do the occasional thrash half way to Chester from Whitchurch in low gear and keep revs up around 3k. I can tell it's doing a regen as temp rises and stays there till it's done - just keep driving till temp drops to normal.
Also put bottle of something in fuel tank to help it along last time. Never see any black soot out the exhaust at all.
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I had an Insignia 2.0 diesel for 9 years from new, and never had an issue with the DFP. From what I remember reading, engine speed above 2000rpm would make the DPF hot enough to self-clean - however, seeing as cruising at 70 was about 1500rpm (I think) it would need a bit of spirited driving every now and then for that to work. Otherwise, it would just start a regen cycle and dump a load of fuel into the exhaust when it needed to (you could watch the consumption go from 0.1 gallons/hour at idle to 0.4).
If you didn’t watch the consumption, you had no way of knowing really as the car didn’t act any different during the cycle - the same couldn’t be said for my previous 3.0 Signum, which went up to 1 gallon\hour and sounded a lot louder.
Motorway cruising isn’t the best for the DPF, it just allows the soot to build up at the slowest possible rate. Urban driving is the worst case scenario.
If it gets really bad, you can just take it off, soak it in some cleaner and jet wash it through. I’ve never had to do it, but plenty of videos online about it.
Interestingly, the first Vauxhalls fitted with a DPF would flash the glow plug light when a regen was occurring - they had so many people come back to the garage thinking it was a fault because they didn’t RTFM that they took it out with a software update. What did happen on the insignias though, was that the rear window heater element would activate at the same time as the regen cycle (I have no idea why) so a mod was created using an LED you could wire into the circuit and then hide in a vent or something which would let you know when it was doing a regen…
If you didn’t watch the consumption, you had no way of knowing really as the car didn’t act any different during the cycle - the same couldn’t be said for my previous 3.0 Signum, which went up to 1 gallon\hour and sounded a lot louder.
Motorway cruising isn’t the best for the DPF, it just allows the soot to build up at the slowest possible rate. Urban driving is the worst case scenario.
If it gets really bad, you can just take it off, soak it in some cleaner and jet wash it through. I’ve never had to do it, but plenty of videos online about it.
Interestingly, the first Vauxhalls fitted with a DPF would flash the glow plug light when a regen was occurring - they had so many people come back to the garage thinking it was a fault because they didn’t RTFM that they took it out with a software update. What did happen on the insignias though, was that the rear window heater element would activate at the same time as the regen cycle (I have no idea why) so a mod was created using an LED you could wire into the circuit and then hide in a vent or something which would let you know when it was doing a regen…
In my experience it isn't a massive issue - we run a fleet of diesel vehicles at work doing all kinds of different uses and generally abused - over several years even the ones only doing like 3x 2-3 mile runs a day in rush hour traffic haven't had DPF issues - EGR getting gunked up happens a bit though especially on the ones which don't get a good run now and again.
Yeah I do think it's a none issue now. And only ever had one car have the EGR issue but think was the Qashqai and funny enough the one used for longer journeys daily.
Funny enough mostly seems to be the Nissans, including my pickup, which have had EGR issues.
Most of the newer vehicles state something like avoid frequent journeys of <10 minutes, <10 MPH average speed to avoid excessive DPF build up whereas older ones would be something like 15-20 minutes average speed under 40-50 would result in excessive build up.
Agreed, my Scania HGV has never once done a regeneration in its 300k miles and 4 years of life, predominately, it lives on the motorway cruising….
From what I’ve learned with my DPF equipped Volvo V70 D5, the crucial aspect of a regeneration is the amount of time the engine is running for at normal operating temperature for it to complete the cycle, combined with decent fuel.
When I first got the car it kept giving me this message.
I was using supermarket diesel, since I’ve changed to V-Power diesel,and not my driving style or routine, it’s not come on once in over 5k miles.