More complicated than that, and nobody said that the fuel is the result of air flow, nor that MAFdictates anything just that it's part of the fuelling strategy the ECU has strategies for each stage of the engine's activity, the magic term is "addaptive strategy" which begins when the vehicle is already moving and then all the sensors come into play, including MAF
wammers said:
The RPM is a result of injected fuel, the airflow a consequence of the RPM. You cannot take an airflow reading at any RPM then surmise that the fuel being injected is a result of that airflow. It isn't. The reverse engineering people have it the wrong way around. ;)
Click to expand...
isnt that so for petrol engines too? cos then no need for MAF on those either
I wanted to keep that truce but as you quoted me twice on the same post i couldnt help myself... i hope i'll be able to rest my case from now :(
 
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bankz5152 said:
@sierrafery this is the MAF "boost box" no idea if its any good or not, though you may find it interesting.

http://www.diablodemon.co.uk/TD5_Tunning_information/td5_tunning_information.html
Click to expand...
I dont like any device which tricks the ECU, at least they found a good name for those tricking devices (if we take the pejorative meaning of the word "demon" :cool:)... IMO better drive it with MAF unplugged than give the ECU false readings...unless you have an EGT gauge to be on the safe side

though i'm wondering why would they make such device then tell you to bypass the EGR:confused: ... cos it seems that then the MAF becomes useless and has nothing to do with fuelling.... according to the diesel engine demon(with the positive meaning of "demon" here) :)
 
sierrafery said:
I dont like any device which tricks the ECU, at least they found a good name for those tricking devices (if we take the pejorative meaning of the word "demon" :cool:)... IMO better drive it with MAF unplugged than give the ECU false readings...unless you have an EGT gauge to be on the safe side

though i'm wondering why would they make such device then tell you to bypass the EGR:confused: ... cos it seems that then the MAF becomes useless and has nothing to do with fuelling.... according to the diesel engine demon(with the positive meaning of "demon" here) :)
Click to expand...

haha I've no idea! Im still trying to get my head around Td5 management beyond "this bit does that" lol

Same, my 110 runs so much better with the uprated MAP sensor instead of the boost box. EGT Gauge is on the cards, though got a couple things I want doing first.
 
sierrafery said:
More complicated than that, and nobody said that the fuel is the result of air flow, nor that MAFdictates anything just that it's part of the fuelling strategy the ECU has strategies for each stage of the engine's activity, the magic term is "addaptive strategy" which begins when the vehicle is already moving and then all the sensors come into play, including MAF
isnt that so for petrol engines too? cos then no need for MAF on those either
I wanted to keep that truce but as you quoted me twice on the same post i couldnt help myself... i hope i'll be able to rest my case from now :(
Click to expand...

You really don't have a bloody clue do you? Stop talking rubbish and there will be no need to comment. Electronic fuel injected petrol enginel need a MAF because they work on a constant stoichiometric mixture ratio. They are throttled by air, fuel is injected subject to airflow to maintain that ratio at all RPMs. Diesels do not, they are throttled by fuel the do not need a MAF other than for EGR feedback.
 
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I'm asking again cos it seems you didnt get my question, or you did?
wammers said:
The RPM is a result of injected fuel, the airflow a consequence of the RPM. ... The reverse engineering people have it the wrong way around.. ;)
Click to expand...
no he didnt, just that IMO you dont undertsand what an addaptive strategy is and that the Td5 ECU has different strategies:
1. for cold start
2. for hot start
3. for idle/wide open throttle
4. for acceleration
(for 1 and 2 the ECU uses mapped information stored in EEPROM and only CKP, ECT and FT readings) and all the abobe are part of the addaptive strategy when MAF reading will be used amongst all the other sensors and compared to stored mapped information as to calculate optimal fuelling for acceleration...that's why they are sluggish with bad MAF or the EGT goes in the sky not cos the ECU is "confused"

then i asked if it isnt so for petrol engines too?(I mean the bolded pat in the first quoted theory) which i agree with but you started to be rude again without answering to that... cos then
wammers said:
Electronic fuel injected petrol enginel need a MAF because they work on a constant stoichiometric mixture ratio. They are throttled by air, fuel is injected subject to airflow to maintain that ratio at all RPMs.
Click to expand...
so aply your first theory to the second one and explain how will be airflow on a petrol engine without any RPM then to calculate the ratio?... and dont tell me again how the diesel or petrol engine is throttled PLEASE :cool: , i'm speaking about apples and you about pears here

i won't contradict you ever about how the ENGINE is throttled but better dont contest something which is demonstrated by a skilled electronist with graphics and live readings(not me, the reverse engineering guy).... unless you can contradict those studies with others of the same kind.
 
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Can I attempt a summary.
You both agree that the diesel is throttled by fuel but Fery is suggesting that the MAF, amongst others, is used to tweak the amount of fuel required to meet throttle demand.
Or something....
 
sierrafery said:
I'm asking again cos it seems you didnt get my question, or you did?

no he didnt, just that IMO you dont undertsand what an addaptive strategy is and that the Td5 ECU has different strategies:
1. for cold start
2. for hot start
3. for idle/wide open throttle
4. for acceleration
(for 1 and 2 the ECU uses mapped information stored in EEPROM and only CKP, ECT and FT readings) and all the abobe are part of the addaptive strategy when MAF reading will be used amongst all the other sensors and compared to stored mapped information as to calculate optimal fuelling for acceleration...that's why they are sluggish with bad MAF or the EGT goes in the sky not cos the ECU is "confused"

then i asked if it isnt so for petrol engines too?(I mean the bolded pat in the first quoted theory) which i agree with but you started to be rude again without answering to that... cos then

so aply your first theory to the second one and explain how will be airflow on a petrol engine without any RPM then to calculate the ratio?... and dont tell me again how the diesel or petrol engine is throttled PLEASE :cool: , i'm speaking about apples and you about pears here

i won't contradict you ever about how the ENGINE is throttled but better dont contest something which is demonstrated by a skilled electronist with graphics and live readings(not me, the reverse engineering guy).... unless you can contradict those studies with others of the same kind.
Click to expand...

You don't understand how a diesel engine works. You don't understand how a petrol works. What exactly is different in your 1 to 4 above from a EDC ECU fitted to a diesel engine that doesn't have a MAF sensor? You read bumph on the net don't understand what you are reading, misinterpret it and quote it as gospel. It is an absolute given that as the fuel is increased to service a power/RPM demand, as the engine speeds up more air will flow through the MAF because it is free flow and not restricted. Only when EGR is active is the reading from the MAF sensor relevant. When a reduced flow indicates to the ECU how much exhaust gas is being ingested, then the ECU modulates various controls to finely adjust the combustible air to exhaust gas ratio to give clean combustion and reduce Nox without smoke. Tell me what is it you do or did for a living? From some of the question you have asked, and some of the statements you have made, i respectfully suggest if you want work doing on your car, get some who knows what they are doing the carry it out.
 
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I will not dignify that with an answer, it's in my profile page, i'm quoting as gospell only things i can understand and i believe, i'll quote you too when somebody will tell that the diesel engine is not throttled by fuel :cool:... now that i know the correct term i repeat it's like "apples and oranges" but i can be rude too and tell you that you dont have a clue about applied electronics or electronic engine managements if you compare a rudimentary EDC with an EEPROM based addaptive management
wammers said:
...What exactly is different in your 1 to 4 above from a EDC ECU fitted to a diesel engine that doesn't have a MAF sensor?...
Click to expand...
the difference is huge but only somebody trained in electronics could understand , not the case for you, btw i've been fixing with success everything electrical on my own cars and friend's for the last 25 years.:rolleyes:
 
sierrafery said:
I will not dignify that with an answer, it's in my profile page, i'm quoting as gospell only things i can understand and i believe, i'll quote you too when somebody will tell that the diesel engine is not throttled by fuel :cool:... now that i know the correct term i repeat it's like "apples and oranges" but i can be rude too and tell you that you dont have a clue about applied electronics or electronic engine managements if you compare a rudimentary EDC with an EEPROM based addaptive management

the difference is huge but only somebody trained in electronics could understand , not the case for you, btw i've been fixing with success everything electrical on my own cars and friend's for the last 25 years.:rolleyes:
Click to expand...

Good for you. I don't profess to have a clue about applied electronics but i do know how a diesel works and it does not need a MAF sensor to be controlled electronically. Only EGR with feedback needs a MAF sensor. Only difference i can see about newer ECUs is that they can be programmed in situ whereas the older ones could not be and needed a new chip. But they both do the same job.
 
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