[Genoa1893]

Hi there,
I-m finally going to install my progressive WI kit. Now, it happens I have a DPF equipped car (a 2.0 TDI PD). Should I expect troubles as WI lower exhaust temp (but I guess this only when nozzles sprays?).

Stefano

[dvldoc]

We have heard of no issuse with DPF vehicles, The data behind how they work is kind of limited. Here's the deal with the water injection it will reduce the particulates in your emissions about 65 to 80%. If you reduce combustion temps below 2300F you get a huge drop in hydrocarbon formation as this is around the limit they start to from, IE Soot. You could put a old non-electronics Pajero with water injection against any DPF fitted car and it would will have lower emissions hands down.

But like stated there should be no adverse affects.

system utilizes a porous silicon carbide substrate. It also includes an oxidation catalyst upstream of the filter. Regeneration of the filter, which occurs every 400-500 km, is controlled by the common rail injection system. Multiple post-injections of fuel during the regeneration period increase the combustion temperature. The oxidation catalyst oxidizes unburnt hydrocarbons generated by the post-injections, releasing additional quantity of heat. Both effects increase the exhaust gas temperature to about 450°C. A fuel additive (cerium based Eolys by Rhodia) is used to lower the combustion temperature of soot, allowing the filter to regenerate at temperatures below 450°C. The additive is stored on the vehicle and automatically dozed. After every 80,000 km the filter must be cleaned from the additive ashes by flushing with water, and the additive replenished. Peugeot said it invested 400 million francs ($66 million) to produce the filter system. Particulate traps were first introduced to German cars sold in California in the 1980's. Due to technical problems traps were quickly abandoned and have not been used on diesel cars since that time. The Peugeot would be first modern, mass-produced automobile equipped with a diesel particulate filter. Particulates are perceived as one of the most troublesome of diesel emissions. Carmakers are under increasing pressure from environmental regulatory authorities, both in EU and in the U.S., to reduce the particulate emissions. For example, emission levels specified by the newly adopted California LEV II standard (year 2004) appear to be impossible to meet without diesel particulate filters.

[Genoa1893]

These are good news, thank you!
So I hope I'll have my kit installed in a few weeks on my already remapped Octy and will get you back.

Stefano

[tweak'e]

have a search around on the net. there is a good doc on direct cylinder water injection for emmision purposes. basicly it dampens down the burn so flame temp is to low for Nox to be created. however it was noted that manifold injection required far more water to achive it.
unfortunatly i cannot remember if the lowing of the flame temp caused increased soot production which is typical when EGR is used.
i doubt that with the small amount of water you would be useing it wouldn't be enough to drop flame temp low enough.

[Genoa1893]

I'm planning plan to remove EGR by venting to air and using EGR "plug" for the pre-turbo nozzle. This way I should get even less soot, shouldn't I?

[tweak'e]

blocking off egr will certainly reduce the soot and help keep your intake clean.
however just be aware that blocking off egr will give more push on the turbo. the variables tend to overboost unless you change the way its controlled.

[Genoa1893]

hmm, good!
Rather than blocking egr (I guess it would throw a CEL if not adjusted) I would let it vent to atmo, and just avoid warm air to enter the turbo, that's why it should spool before (and push more?), correct?

[nutron]

I read a large amount of data from varying sources and they all suggested that soot production was reduced by water injection at low to medium loading only. At high engine loads the soot output actually increased but Nox output was alwasy lowered.

[tweak'e]

Originally Posted by Genoa1893 hmm, good! Rather than blocking egr (I guess it would throw a CEL if not adjusted) I would let it vent to atmo, and just avoid warm air to enter the turbo, that's why it should spool before (and push more?), correct?

i'm not sure on the ECU on those. most of the ones i know of you can block egr without eror codes. however if its one that checks for correct egr operation you may hav to vent it back to exhaust system. that would also men you won't get any overboost (egr valve will act like a wastegate).
it may still get an error code if it can work out that there is no egr flow into the intake.
i know some where getting around it by partly blocking the egr. it still flowed enough egr for the ecu to think its working fine.

[Genoa1893]

Thank you,
I've read that with vag-com you can deactivate egr, but thought that just disconnecting the pipe and missing the EGR inlet wouldn't be "perceived" by ECU, while I bet that blocking the pipe emitting the egr flow is monitored. I seem that Basil did so.