A DPF thread. New DPF fitted, car will not recognise it.
Discussion
I doubt it's glow plugs.
If 3 are working and one isn't it's unlikely the ECU will be able to tell one plug has gone down, as they are usually mounted in parallel from the same loom.
My personal course of action would be to measure the DPF differential pressure sensor. A good unit would have a DP of something about 2 - 4 mbar.
If this is good, the DPF light shouldn't be on. It's a software fault. Back to Honda for a jump up and down.
If you can't get a sensible reading, then the electrical connection to the ECU is in trouble. No options other than to painstakingly check it. (It's possible to use capacitance to check if you have the kit, and the patience).
Or if the readings are sensible but high, then either the pipes are damaged, or the sensor is damaged, or the DPF is blocked.
Depending on what's going on, I would be tempted to gut the DPF, remap it, and never use it on the road again. (because of course that would be socially irresponsible and wholly inadequate).
If 3 are working and one isn't it's unlikely the ECU will be able to tell one plug has gone down, as they are usually mounted in parallel from the same loom.
My personal course of action would be to measure the DPF differential pressure sensor. A good unit would have a DP of something about 2 - 4 mbar.
If this is good, the DPF light shouldn't be on. It's a software fault. Back to Honda for a jump up and down.
If you can't get a sensible reading, then the electrical connection to the ECU is in trouble. No options other than to painstakingly check it. (It's possible to use capacitance to check if you have the kit, and the patience).
Or if the readings are sensible but high, then either the pipes are damaged, or the sensor is damaged, or the DPF is blocked.
Depending on what's going on, I would be tempted to gut the DPF, remap it, and never use it on the road again. (because of course that would be socially irresponsible and wholly inadequate).
Muldoonsghost said:
Right now I'm soaking the plugs in Liquid Wrench, supposedly the worlds best corrosion shifter. Better than WD40 that's for sure. A few days of soaking will, I hope, make it easier to remove. I intend to call a company on Monday to replace the set but what do these specialists do if one breaks on them? Say tough, or is drilling out included? One to ask the company I guess.
The specialoist comapnies remove broken injectors and glow plugs...it's kinda what they do and why they're specialists at it.If you're just paying someone to try and change them that's a different matter. But it is just a reality that some will be stuck and can break. And in turn, why specialists exist to remove them in-situ.
And as for Bearman, yes, most modern cars can easily identify which glow plug is an issue as they are not simply all wired together. In fact that's very rare now. They might be in pairs, or individually and PWM controlled for faster heat up as well as so they can operate them under other conditions than simply cold starts.
Nothing much to add except both Steve’s know their onions and turbo definitely does.
So please listen to their advise as it’s not costing you a penny so you can then make a better informed decision.
I’m no master tech but you’ve had good sound advice by far more knowledgeable folk than others including me
So please listen to their advise as it’s not costing you a penny so you can then make a better informed decision.
I’m no master tech but you’ve had good sound advice by far more knowledgeable folk than others including me
drdino said:
Has it been scanned with a proper diagnostic tool? If so, what DTCs is it showing?
Showing my ignorance, what are DTC's? I don't have, as has been discussed, a 'proper' diagnostic tool and it costs more money each time another go is had by a garage. I just have the Torque app on an eBay OBDII Bluetooth connection.stevemcs said:
Given it’s had a new dpf the soot and ash content make no difference. Something is stopping it from a regen.
Indeed. This link says
https://www.injector-removal-service.co.uk/seized-...
"Further more, more recent revisions or “regulation requirements” to diesel engines mean these vehicles are now fitted with Diesel Particulate Filters, which, for maintenance purposes, require the glow plugs to be turned on at certain “regeneration” modes while the engine is running increasing combustion temperatures which works as an effective method to clean the exhaust DPF."
blank said:
If you can find the information out you can add "custom PIDs" in Torque to read things like DPF pressure difference, Ash Content etc.
Have a hunt around on owner forums as someone may have done this before for your engine.
Thanks, interesting. I'll do that later this evening. Have a hunt around on owner forums as someone may have done this before for your engine.
shakindog said:
Nothing much to add except both Steve’s know their onions and turbo definitely does.
So please listen to their advise as it’s not costing you a penny so you can then make a better informed decision.
I’m no master tech but you’ve had good sound advice by far more knowledgeable folk than others including me
I agree, this place (Piston heads) has many great contributors and I appreciate each word I get from them. So please listen to their advise as it’s not costing you a penny so you can then make a better informed decision.
I’m no master tech but you’ve had good sound advice by far more knowledgeable folk than others including me
stevemcs said:
It doesn't matter if only one glowplug has failed, the car see's a fault and thats enough to stop it from carrying out a regen
As I posted earlier a website says..."Further more, more recent revisions or “regulation requirements” to diesel engines mean these vehicles are now fitted with Diesel Particulate Filters, which, for maintenance purposes, require the glow plugs to be turned on at certain “regeneration” modes while the engine is running increasing combustion temperatures which works as an effective method to clean the exhaust DPF."
stevieturbo said:
The specialoist comapnies remove broken injectors and glow plugs...it's kinda what they do and why they're specialists at it.
If you're just paying someone to try and change them that's a different matter. But it is just a reality that some will be stuck and can break. And in turn, why specialists exist to remove them in-situ.
And as for Bearman, yes, most modern cars can easily identify which glow plug is an issue as they are not simply all wired together. In fact that's very rare now. They might be in pairs, or individually and PWM controlled for faster heat up as well as so they can operate them under other conditions than simply cold starts.
I'm on the South Coast, near Brighton. Local garages don't want to know (so far) and the 'specialists' don't seem to cover this area. Well, one London company said they would come down to remove a broken injector for... £450 each. Still searching for a specialist.If you're just paying someone to try and change them that's a different matter. But it is just a reality that some will be stuck and can break. And in turn, why specialists exist to remove them in-situ.
And as for Bearman, yes, most modern cars can easily identify which glow plug is an issue as they are not simply all wired together. In fact that's very rare now. They might be in pairs, or individually and PWM controlled for faster heat up as well as so they can operate them under other conditions than simply cold starts.
stevemcs said:
You need to ask them, but normally they drill them out
But at extra, unknown, cost. My worry is I ask for all 4 to be replaced. Maybe 2 of them break. Then they want another £300 each to repair the broken 2 on top of the money already spent and I have no choice as the engine doesn't run. The price of owning a car I guess.My thanks to you all for your contributions. It now seems as if the glow plugs have likely been an issue for some time. There is a hand written note on the top of an old invoice for trying to cure 'fumes in the cabin' saying "glow plugs". It seems to be common knowledge in some places that they are needed for regen, but not at a Honda main dealer? Or another large (5+lifts and more bays) garage I visited?
Anyway, I'm soaking the plugs in Liquid Wrench daily and I'm looking for someone to come in and replace all 4. if THAT doesn't allow the DPF to regen then I'll start by screaming. Loudly...
So, to continue searching.
Anyway, I'm soaking the plugs in Liquid Wrench daily and I'm looking for someone to come in and replace all 4. if THAT doesn't allow the DPF to regen then I'll start by screaming. Loudly...
So, to continue searching.
Merc V6 diesels like to snap glowplugs, mercedes use a snapping torque, so instead of tightening to say 40nm, yiu use a torque wrench set at say 40nm to undo them that way the torque wrench clicks off before breaking the plug. The issue with glowplugs is the build up of carbon on the tip that can prevent the plug being removed.
Have a read up on Subarus boxer diesel engine and how to remove the glow plugs, some say plus gas, hot engine and an impact driver.
Have a read up on Subarus boxer diesel engine and how to remove the glow plugs, some say plus gas, hot engine and an impact driver.
There is a software fault on some Hondas that can mean you can’t read certain codes and resetting it is very difficult. I had some fun and games with my wife’s 2015 Honda Civic. One failed glow plug will cause these issues as the ecm uses the glow plugs during regen, a glow plug had failed and it was failing to regenerate the dpf so I’d be asking the dealer to sort out the duff glow plug and check the ecm software is the issue.
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