Sensors; Lambda, IAT and Water Temperature

Anything to do with the 1200 Corsaro series
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BumbleBee
Posts: 233
Joined: 13 Jun 2017 21:10
Location: Reading

Sensors; Lambda, IAT and Water Temperature

Post by BumbleBee »

Hi All,
Newbie to fuel injection on the 1200 engines here. Looking for some clues about the relationship between the Lambda, Inlet Air Temperature and Water Temperature sensors. I mean I know what each one measures. But it seems to me the outputs from them is maybe used to do the same thing e.g. adjust the fuel:air mixture. So are those outputs used all the time or are some sensor outputs only used some of the time? Or maybe some take priority over the others?
Ebi
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Joined: 19 Sep 2016 06:19
Location: Stuttgart

Re: Sensors; Lambda, IAT and Water Temperature

Post by Ebi »

Hi Bumblebee,
there are various parameters which have an effect to the fuel quantity and ignition timing:
- ambient temperature
- engine (water) temperature
- throttle position
- air pressure
- engine speed / rpm
- front or rear cylinder
- lambda value (if a lambda controlled map is used)

There are maps and tables for each parameter in the ECU software, the parameters are constantly read and processed. The result of this process is one fuel injection and one ignition timing value for each ignition and cylinder, front and rear - they are a little bit different, because the temperature is different.

The complete ECU content is available as a binary file. With tools like TunerPro it is possible to interpret this file, as long as it is known at which position the maps, tables and some flags are located. This pointer information is stored in a TunerPro XDF interpretation file.
It is possible to edit and modify the maps and tables to optimize fuel consumption, engine power or throttle response on a dyno.

Some examples of interesting modifications:
- activate/deactivate lambda control
- modify fan activation temperature
- modify engine speed limiter
- flash a complete ECU file with better fuel efficiency and smooth engine behaviour at low rpm

There is a lot you can play - the playground is open :mrgreen:

Regards
Ebi
BumbleBee
Posts: 233
Joined: 13 Jun 2017 21:10
Location: Reading

Re: Sensors; Lambda, IAT and Water Temperature

Post by BumbleBee »

Does low Oil Pressure at the sensor, cause any effect on the fueling e.g. during starting or running?
morini_tom
Posts: 1096
Joined: 05 May 2006 13:47
Location: Northampton
Location: Northampton

Re: Sensors; Lambda, IAT and Water Temperature

Post by morini_tom »

I don’t know but I wouldn’t think so.

In its running in period I had a few low pressure warnings (rectified at first service with a new sensor) and I didn’t notice any difference in the way it ran.

More sophisticated engine control systems might restrict power to prevent any engine damage that could be caused by low oil pressure, inactivation of piston cooling jets or inability to phase camshafts etc but our engine doesn’t have those things.

As the rider it’s our responsibility to see the low pressure warning and moderate our right wrist movement accordingly. It’ll fuel for the air you give it.

Why, are you having issues?
BumbleBee
Posts: 233
Joined: 13 Jun 2017 21:10
Location: Reading

Re: Sensors; Lambda, IAT and Water Temperature

Post by BumbleBee »

No oil issues no. Probably just a consequence of trying to learn something new :D
BumbleBee
Posts: 233
Joined: 13 Jun 2017 21:10
Location: Reading

Re: Sensors; Lambda, IAT and Water Temperature

Post by BumbleBee »

Without knowing it, I have been running the fuel injectors at lower than normal voltages, due to an electrical problem. I'm thinking of putting some injector cleaner through the fuel system in case crud has formed at the nozzles.
morini_tom
Posts: 1096
Joined: 05 May 2006 13:47
Location: Northampton
Location: Northampton

Re: Sensors; Lambda, IAT and Water Temperature

Post by morini_tom »

How low a voltage were you running do you think? And where do you suspect the low voltage was- in the whole system or just certain components?

The delivered injector pulsewidth will be compensated for battery voltage to still deliver the correct fuel mass so won’t have had any ill effect in my opinion.

If other parts of the electrical system were not seeing the same voltage drop then I suppose you could have had some mismatch between for example measured lambda values and air and fluid temperatures which could create some unusual behaviour, but quite unlikely I think.

Port injectors are nowhere near as susceptible to crudding up as direct injectors as they don’t see the heat and combustion byproducts that DI injectors do in the combustion chamber, and they aren’t as sensitive to low voltages either due to the much longer pulsewidths compared to high pressure direct injection.

Injector cleaner can have its benefits but can also be a bit snake oil. If you stick with a known brand it probably won’t do any harm though- although keep in mind our plastic fuel tanks- it’s worth doing your research to ensure compatability.

Personally I’d fill it with decent fuel with as low an ethanol content as possible and give it a good thrashing. Hard to do on the road on a 1200 but some good heat cycles and an Italian tuneup always helps
BumbleBee
Posts: 233
Joined: 13 Jun 2017 21:10
Location: Reading

Re: Sensors; Lambda, IAT and Water Temperature

Post by BumbleBee »

Voltages anywhere from normal down to low enough to stop the bike from running. Caused by a slowly corroding wire at the 12V output connector from the regulator. That led to the generator gradually not being able to keep up with the electrical demands of the bike. It certainly ran badly below 3000 rpm.
I hear what you say about port injectors not crudding up like direct injectors do. I hadn't realised the bit about pulse width doing some compensating. Thanks for that.
BumbleBee
Posts: 233
Joined: 13 Jun 2017 21:10
Location: Reading

Re: Sensors; Lambda, IAT and Water Temperature

Post by BumbleBee »

Does low ethynol fuel cause less deposits, or are you saying that because its just better quality fuel Tom ?
morini_tom
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Location: Northampton
Location: Northampton

Re: Sensors; Lambda, IAT and Water Temperature

Post by morini_tom »

I’m actually an advocate for ethanol fuels, in the correct application they have their benefits. Much of the issue people have (setting scaremongering aside) is due to using ethanol fuels in a vehicle not fully designed for it- it’ll run, but how well and for how long is the question.

It’s a bit like the switch to unleaded fuels a few decades ago- some vehicles protested and ate their valve seats, some vehicles suffered seemingly no ill effects (aircooled Morini included!), some companies got rich selling snake oil miracle potions and expensive conversions (sometimes necessary ones sometimes not)

In the case of our 1200s my view with regards ethanol fuels is the following:

1) they were designed and released into market in the early 2000s when ethanol fuels in Europe were a distant possibility
2) most have plastic tanks and generally speaking ethanol and the wrong type of plastic tanks don’t mix. Low ethanol content is probably ok but one issue is leaving the fuel in the tank for a long period and the ethanol separating out. Most of our 1200s are not exactly daily rides and mine can sit months idle. I’d rather have E0 in the tank if at all possible. Our tanks might be ok but Ducatis of the same era suffered badly in the USA in particular, and more recent corsaros went back to metal tanks so that says something. For me it’s not worth the risk to find out.
3) ethanol fuels require more fuel injected for a given mass of air than pure gasoline. Our engine management system is fairly basic. The engine was mapped for the market fuel at the time, more than likely E0. So running with ethanol in the fuel will cause it to be lean of where it should be. The lambda sensor can of course trim this fuelling error and adapt the injected fuel mass back to something near correct, however not all 1200s actually have the closed loop lambda turned on. Mine doesn’t and that’s how I took delivery of it brand new… so with E10 it will run not insignificantly lean of where it should be.
4) as per point 3 the amount of extra fuel required at start (choke to put it in carburettor terms) is significantly more for ethanol fuels than gasoline, much more than them just the difference in stoichiometric ratio. As a result starting will be poorer unless the calibration is adjusted accordingly.


These reasons alone are enough for me to want to avoid putting ethanol fuels into my Corsaro.

In terms of your question about deposits and fuel quality, that’s a difficult question as it’s very specific to a particular fuel blend- ethanol isn’t so much the driving factor here, more what other additive packs are in the fuel and what the fuel base stock is. Ethanol can be used to increase the RON of an already high RON fuel which has its benefits (again, in the right application) so ethanol content doesn’t necessarily mean low quality fuel. Personally I tend to stick to one premium brand of fuel where I can, and tend to use super. You’ll never know what additive packs exist in say v power or ultimate but it’s reasonable to take the view that you get what you pay for, and the additives do do a decent job of cleaning up combustion. Even then the actual dispensed fuel will vary seasonally and based on other factors but it’s the best you can do as a consumer
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