Hello there ,

I am wondering is there a way to decrease IQ injected at idle when car is not moving on edc15/edc16 ecu-s?
Which part of ecu is controling how much IQ at which temperature will be injected at idle ?
I want to make economy map when car is 99% city driving and idle is big part of fuel consumption.
Every help is welcome :)

Regards Sasa

You must understand - in iddle ecu inject fuel need for save iddle rpm. You can't inject less because rpm will decrease. Decrease rotation resistance and injection will decreased too.

So for economy map there is no way to save some fuel at idle ?

I see only one possible way to decrease fuel consumption on iddle by firmware modification - play with SOI on iddle. CR engines often have late injection on iddle for decrease noise. This SOI not optimal for economy. You can advance iddle SOI but you engine will sound hard as old diesel.
Other way not chiptuning. Decrease resistance of output and input systems, decrease engine load (electrical consumption, clima etc.).

Thanks for reply mate, I already played with SOI and got good results, just thought that maybe can do more with limiting idle somehow :)

Sasanis wrote:Thanks for reply mate, I already played with SOI and got good results, just thought that maybe can do more with limiting idle somehow :)

you can make combination of increasing rail pressure - by increasing rail pressure you get similar effect as changing soi.

higher rail pressure - shorter injection duration, same injection qty - earlier eoi
adding soi - same injection duration, same injection qty - earlier eoi

Just wondering what difference that would give. When I look at consumption at idle it's in l/hr, turning of airco gives -0.1l/hr. I think in the idle area it's not really interesting to change something. The biggest consumption is in the acceleration after a stop.

economy remap - soi, duration, turbo pressure, turbo vanes, drivers wish...

Imho simplest way to save some fuel in city on EDC16 is to reduce fuel injected, this can be done as you don't want maximum power in city if you want lower consumption.

For example on 80kW HDI you can do 2 things:

1. At 20 - 40% engine load in range 1100 up to 3100 rpm you can safely reduce injected fuel while accelerating up to even -20%.

In case of gentle driving under 2500 rpm this will result in up to 1 liter per 100 km less consumption, but car will be way sluggish. To compensate for "sluggishness" you can add 15% to 6% from 1300 up to 2500 rpm in part injection maps only for 2,2 to 3,9 volt MAF range, not touching larger flow range.

2. Reduce part throttle injection map values for some percentage in all ranges except (idle) and range you compensated for sluggishness (in point 1). Adjust injection extension maps to match part throttle changes for quietest and smoothest running.

Hello wise people,

I've upgraded my nozzles on my edc16c31 3.0d from 216 to 219 model, original euro 4 204hp to euro 4 272hp.
All good, good power no smoke after updating the injection timings and some SOI.

But I have a bad smell and some smoke on idle, how can I lower my IQ at idle? My car is MUFless.Right now its 7mg per stroke and i want to go to 5mg to see if still smells bad, mostly when hot.

Thank you all, great inspirational site