Synergie 2.0i Hdi
Discussion
Hi all,
Anyone out there with any experience of the Hdi engine? My pronlem is that the car has failed the MOT on the emissions test. My mechanic is flushing out the engine and replacing the oil etc to see if that will cure my problem. When the engine is rev'd to the limit as per the test, plumes of black smoke appear from the exhaust. This is not noticable during normal driving. Any ideas.
Many thanks
Al
Anyone out there with any experience of the Hdi engine? My pronlem is that the car has failed the MOT on the emissions test. My mechanic is flushing out the engine and replacing the oil etc to see if that will cure my problem. When the engine is rev'd to the limit as per the test, plumes of black smoke appear from the exhaust. This is not noticable during normal driving. Any ideas.
Many thanks
Al
Thanks for your reply. My mechanic has flushed the oil, replaced the air filter which was well over-due for replacement and added fuel cleaner. I took it for a spin up and down the motorway.When I got back to the garage we checked the smoke again and it did appear to be cleaner. My mechanic added fuel cleaner again to the fuel filter. I am going to take it to work tonight and the have it re-tested tomorrow, fingers crossed!!
Riker18 said:
Hurray, it's passed it's MOT. A good clean of the injectors, filters etc is all it needed!!
My mechanic recommends the use of Millers Diesel + Cleaning solution added to each fill-up!!
Cheers guys
My mechanic recommends the use of Millers Diesel + Cleaning solution added to each fill-up!!
Cheers guys
It's funny really that they fail, because the intake uses an air flow meter, yet a bunged up filter will make them smoke.
Surely if the filter is bunged up so that less air is passing (why it's running rich), then it'd detect that less air is going in?
Weird these Pug engines. The more you look at their ECU inputs the crapper they get
If they had a Lambda sensor or Air Fuel Ratio sensor then they'd be alot better!
Dave
Mr Whippy said:
If they had a Lambda sensor or Air Fuel Ratio sensor then they'd be alot better!
Not very useful on a diesel, as AFR varies with throttle setting and is still about 50% lean of stoichiometric at full throttle. The maximum fuelling ratio is set by the "black smoke limit" - if you go richer than this it smokes. If there's an air flow meter it should keep the fuelling below the black smoke limit. It could be that it is attempting to do this but the black smoke limit has got lower due to injectors needing cleaning, carbon buildup in the combustion chamber, or whatever; it could be that it has a WOT fuelling strategy that's set for power and is not too clever about smoke; or it could be soot buildup in the exhaust tract burning off at high load, in which case a good Italian tuneup should sort it
Still, surely at around 15:1 AFR the diesel starts to smoke?
I'm meaning purely as a smoke counter measure.
My before and after remap dyno's showed just values as low as 16:1, and it didn't smoke.
Post remap the AFR dropped to 13:1 at points (2000rpm) and the car smoked heavily here too.
Just thinking for what it is it'd let the engine know more about what was actually going on than what it thought? Is an air mass meter or flow meter really that effective? Especially since this engine doesn't even have a boost sensor or intake air (boosted) temp sensor!!!
Dave
I'm meaning purely as a smoke counter measure.
My before and after remap dyno's showed just values as low as 16:1, and it didn't smoke.
Post remap the AFR dropped to 13:1 at points (2000rpm) and the car smoked heavily here too.
Just thinking for what it is it'd let the engine know more about what was actually going on than what it thought? Is an air mass meter or flow meter really that effective? Especially since this engine doesn't even have a boost sensor or intake air (boosted) temp sensor!!!
Dave
You sure they didn't get your charts mixed up with a petrol engined car? Those are petrol engine figures. I wouldn't expect to see anything richer than about 20:1 for a diesel (excepting tractor pulling and the like). And certainly not 13:1 which is richer than stoich (but could be a max power point for a petrol engine). If those figures are correct then I'll have to admit complete bafflement.
Pigeon said:
You sure they didn't get your charts mixed up with a petrol engined car? Those are petrol engine figures. I wouldn't expect to see anything richer than about 20:1 for a diesel (excepting tractor pulling and the like). And certainly not 13:1 which is richer than stoich (but could be a max power point for a petrol engine). If those figures are correct then I'll have to admit complete bafflement.
Yep, the exhaust probe was used throughout the run and monitored AFR I assume from the exhaust gas constituents?
It was a Dyno Dynamics roller, so I'm sure some of the operators on PH (Vixpy??) may know exactly what it's measuring?
Either way the car ran clean before and the AFR suggested it was because it was above stoichometric, and then after my remap the ratio's dropped to 13-14 at points around where I got most smoke...
Also, interestingly, the change in ratio at any given rpm was also the same proportion of increase in torque at those rpm's...
All seemed to link up and make sense, but what your saying now leaves me baffled to what they mean too
Will post prints of them if you would like?
Dave
It wasn't *too* bad to be honest once past 2000rpm, infact it was pretty much fine there unless you were really pushing on hard and fast for a good 5 or 10 mins when it started to get hazey...
The main problem was jus tootling around on my commute, going from 40>national at WOT in 5th and smoking a fair bit.
They did try give me smoke free maps, which they did do, but at the cost of power at the top end too, which was where fuelling seemed fine. Infact I'd have more smoke over 3000rpm when I *wanted* power, rather than under 2000rpm where I was perfectly happy...
Off to buy an OBDII port reader and the KPW2000 flash software. Will be mixing my stock 90bhp map, stock upto 1750rpm, then remapped 125bhp map from 2250>5000rpm, and then blend between the values around that 500rpm step.
Yes the torque will not peak as high, and later, but after 2000rpm it'll still be quicker, when I want it to be, but day to day tootling will be clean and efficient as it was stock
Seems silly that they remap and essentially compromise the rpm range that doesn't need to be compromised, and then under-fuel (relatively) where you could get away with more!
Kinda like this (blue lines)
Basically the stock fuelling (best fit AFR lines) are quite telling. Stock (green) is safe, then gets safer. Remap (red) starts off quite agressive then gets safe. My custom curve seen there (blue) oddly, has a best fit line almost flat at 16:1... seems logical to me that that is optimum.
Thats what I'm aiming at anyway... note the AFR "inverse" spike around 2000rpm in stock and remap (red and green)... odd, wonder if they overfuel to help turbo spool for a higher peak torque?
Dave
The main problem was jus tootling around on my commute, going from 40>national at WOT in 5th and smoking a fair bit.
They did try give me smoke free maps, which they did do, but at the cost of power at the top end too, which was where fuelling seemed fine. Infact I'd have more smoke over 3000rpm when I *wanted* power, rather than under 2000rpm where I was perfectly happy...
Off to buy an OBDII port reader and the KPW2000 flash software. Will be mixing my stock 90bhp map, stock upto 1750rpm, then remapped 125bhp map from 2250>5000rpm, and then blend between the values around that 500rpm step.
Yes the torque will not peak as high, and later, but after 2000rpm it'll still be quicker, when I want it to be, but day to day tootling will be clean and efficient as it was stock
Seems silly that they remap and essentially compromise the rpm range that doesn't need to be compromised, and then under-fuel (relatively) where you could get away with more!
Kinda like this (blue lines)
Basically the stock fuelling (best fit AFR lines) are quite telling. Stock (green) is safe, then gets safer. Remap (red) starts off quite agressive then gets safe. My custom curve seen there (blue) oddly, has a best fit line almost flat at 16:1... seems logical to me that that is optimum.
Thats what I'm aiming at anyway... note the AFR "inverse" spike around 2000rpm in stock and remap (red and green)... odd, wonder if they overfuel to help turbo spool for a higher peak torque?
Dave
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