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Best wishes for a better New Year to all, with the hope we'll recover some of the lost cheer.
Best wishes for a better New Year to all, with the hope we'll recover some of the lost cheer.
KE-Jetronic (CIS-E) info & advice
For some time I have posted here at BenzWorld about the KE-Jetronic and how to do quick & targeted diagnosis in case of CIS-E engine issues. I stopped posting in BW’s R107, W124, W201 forums quite a while ago because there was (and still is) simply too much wrong info/advice posted and, unfortunately, no one there corrects it. I continued to post in the W126 forum since there was more interest & trust in my posts. Recently, however, they’re more often ignored and more wrong CIS-E related info/advice is posted & spread in this W126 forum too … (including YouTube videos, of which I commented on one example in post 20 in This Thread) … and no one seems to mind.
Due to these developments, I’ll stop posting at BenzWorld. Forum members who are further interested in my advice in case of CIS-E engine issues can still reach me via private message. If I have time, I’ll help.
I recommend to consider what I’ve posted in this forum … particularly what I’ve posted in my (unfinished) KE-Jetronic Lambda Control Thread ! … Particularly that thread holds widely unknown information that can most likely not be found anywhere else on the internet and that’s very helpful for quick & targeted diagnosis. Unfortunately, it has hardly born fruit here at BW so far. To counter doubts about the correctness of my posts, I’d like to add (for future readers) that my early design engineering career revolved around Mercedes’ CIS-E engines before they went into mass production.
I wish all readers all the best for 2021 … and please help defeat COVID-19 and beware of those who play it down, let alone of those who reject protective measures … and please help defeat the other rampant pandemic too, the one of lies & conspiracy theories … and don’t listen to those who disdain science, without which the products that this forum is about would not exist.
H.D.
Due to these developments, I’ll stop posting at BenzWorld. Forum members who are further interested in my advice in case of CIS-E engine issues can still reach me via private message. If I have time, I’ll help.
I recommend to consider what I’ve posted in this forum … particularly what I’ve posted in my (unfinished) KE-Jetronic Lambda Control Thread ! … Particularly that thread holds widely unknown information that can most likely not be found anywhere else on the internet and that’s very helpful for quick & targeted diagnosis. Unfortunately, it has hardly born fruit here at BW so far. To counter doubts about the correctness of my posts, I’d like to add (for future readers) that my early design engineering career revolved around Mercedes’ CIS-E engines before they went into mass production.
I wish all readers all the best for 2021 … and please help defeat COVID-19 and beware of those who play it down, let alone of those who reject protective measures … and please help defeat the other rampant pandemic too, the one of lies & conspiracy theories … and don’t listen to those who disdain science, without which the products that this forum is about would not exist.
H.D.
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Dear H.D.
Thank you for your efforts and great technical value you provide to the forum.
If you don't mind, I would like to start a private conversation with you regarding my KE problems (M103 300TE) as well as the pending engine swap from another E320 (M104) I'm planning to do because I couldn't get all my other efforts on the M103 to work.
My e-mail is [email protected] as I couldn't find how to start a private conversation here or how else to contact you.
Irrespective, a Happy New Year to you and your family.
Take care
Thank you for your efforts and great technical value you provide to the forum.
If you don't mind, I would like to start a private conversation with you regarding my KE problems (M103 300TE) as well as the pending engine swap from another E320 (M104) I'm planning to do because I couldn't get all my other efforts on the M103 to work.
My e-mail is [email protected] as I couldn't find how to start a private conversation here or how else to contact you.
Irrespective, a Happy New Year to you and your family.
Take care
Attachments
the problem , when someone answer you dont know their knowledge level , so you get a lot of bad answers .i wonder how many retired or not MB techs are here .most of the time the people who need help dont answer simple questions , like what is the basic fuel pressure , even when you tell them how to do it , in case like that i ignore them .For some time I have posted here at BenzWorld about the KE-Jetronic and how to do quick & targeted diagnosis in case of CIS-E engine issues. I stopped posting in BW’s R107, W124, W201 forums quite a while ago because there was (and still is) simply too much wrong info/advice posted and, unfortunately, no one there corrects it. I continued to post in the W126 forum since there was more interest & trust in my posts. Recently, however, they’re more often ignored and more wrong CIS-E related info/advice is posted & spread in this W126 forum too … (including YouTube videos, of which I commented on one example in post 20 in This Thread) … and no one seems to mind.
Due to these developments, I’ll stop posting at BenzWorld. Forum members who are further interested in my advice in case of CIS-E engine issues can still reach me via private message. If I have time, I’ll help.
I recommend to consider what I’ve posted in this forum … particularly what I’ve posted in my (unfinished) KE-Jetronic Lambda Control Thread ! … Particularly that thread holds widely unknown information that can most likely not be found anywhere else on the internet and that’s very helpful for quick & targeted diagnosis. Unfortunately, it has hardly born fruit here at BW so far. To counter doubts about the correctness of my posts, I’d like to add (for future readers) that my early design engineering career revolved around Mercedes’ CIS-E engines before they went into mass production.
I wish all readers all the best for 2021 … and please help defeat COVID-19 and beware of those who play it down, let alone of those who reject protective measures … and please help defeat the other rampant pandemic too, the one of lies & conspiracy theories … and don’t listen to those who disdain science, without which the products that this forum is about would not exist.
H.D.
Bad or no answers from people who come to a forum for help, is a problem, of course. But a bigger problem is wrong info & advice posted by people who again may have picked it up on the internet and think it‘s correct. KE-Jetronic related YouTube videos that are studded with wrong info/advice are deemed professional in this forum … and no one (including “retired or not MB techs“) opposes.
There must be some really clever monkeys in Australia.
… When I was involved in MB‘s CIS-E engines as a design engineer in the 1980‘s, I couldn‘t even convince the factory service manual people in Stuttgart, that it is a bad idea to simply adopt the name “Gemischregulierschraube“ (mixture regulating screw) from the K-Jetronic manual in the KE-Jetronic manual. And I tried hard. I told them that this will lead people to think that the purpose of this adjustment screw is air/fuel mixture adjustment. And - guess what! - even most professional car mechanics think it is. People underestimate the difference between K- & KE-Jetronic regarding function and, particularly, regarding diagnosis. Good luck trying to convince people of the real purpose of this adjustment screw on the KE-Jetronic and of how bad an idea it is to fiddle around with it.Unfortunately, my posts about the KE-Jetronic here at Benzworld are hardly understood either. Maybe native English speakers find my long, nested sentences (as normal in technical literature in German) too tiring to read.
In the 1980‘s, one of the involved Bosch engineers I cooperated with once said to me (clairvoyantly
):“Die KE-Jetronic wird die am wenigsten verstandene Benzineinspritzung sein, egal wie viele Leute behaupten, Sie zu verstehen.“
(The KE-Jetronic will be the least understood gasoline injection system, no matter how many will claim to understand it)
H.D.
so , what do you call this screw , rotating slightly left or right , change the CO .this is where you set the CO when needed .on the KE almost never , it does set itself as long as the basic setting is around 50% .Bad or no answers from people who come to a forum for help, is a problem, of course. But a bigger problem is wrong info & advice posted by people who again may have picked it up on the internet and think it‘s correct. KE-Jetronic related YouTube videos that are studded with wrong info/advice are deemed professional in this forum … and no one (including “retired or not MB techs“) opposes.
There must be some really clever monkeys in Australia.
Unfortunately, my posts about the KE-Jetronic here at Benzworld are hardly understood either. Maybe native English speakers find my long, nested sentences (as normal in technical literature in German) too tiring to read.
In the 1980‘s, one of the involved Bosch engineers I cooperated with once said to me (clairvoyantly
“Die KE-Jetronic wird die am wenigsten verstandene Benzineinspritzung sein, egal wie viele Leute behaupten, Sie zu verstehen.“
(The KE-Jetronic will be the least understood gasoline injection system, no matter how many will claim to understand it)
H.D.
I don‘t know of anything that Bosch published about the KE-Jetronic in the 1980‘s that I haven‘t seen. I partly saw these things even before they were published. The articles that were published to shop owners were mainly written in the interests of shop owners (not car owners). There are things about CIS-E diagnosis that were not published, because not many shop owners would have been interested to invest the necessary time & attention. Of all shop owners & professional mechanics I knew here in Germany in the 80‘s & 90‘s [I knew many and still MB shops around here contact me for CIS-E advice] only very few were really able to interpret the fluctuating Lambda on/off ratio in combination with given symptoms, for instance. Most found it too complicated, even after I showed them how quick & targeted it can make troubleshooting. They preferred not to think so much and rather replaced more parts than necessary. … I‘m always glad to meet representatives of the former, way smaller, group. This forum needs at least one of them … who has the time & patience to deal with all the wrong info & advice that is posted here.
when you had a shop in the 80 , 90 s you had the opportunity to be member of some bosch technical forum , so every month they would mail you a tech brochure .it was called REPORTER .IN THE VOLUME 3- 90 , so published in marsh 90 , you have the k .jetronic fuel management system . this one used the frequency valve .in nice color graphics , explain the whole thing .too many people working on cars are not interested in technologies , they are the parts changers hopping to get lucky .so you can imagine for the DIY that has near zero mechanical aptitude , it become a mission impossible to offer tech help .I don‘t know of anything that Bosch published about the KE-Jetronic in the 1980‘s that I haven‘t seen. I partly saw these things even before they were published. The articles that were published to shop owners were mainly written in the interests of shop owners (not car owners). There are things about CIS-E diagnosis that were not published, because not many shop owners would have been interested to invest the necessary time & attention. Of all shop owners & professional mechanics I knew here in Germany in the 80‘s & 90‘s [I knew many and still MB shops around here contact me for CIS-E advice] only very few were really able to interpret the fluctuating Lambda on/off ratio in combination with given symptoms, for instance. Most found it too complicated, even after I showed them how quick & targeted it can make troubleshooting. They preferred not to think so much and rather replaced more parts than necessary. … I‘m always glad to meet representatives of the former, way smaller, group. This forum needs at least one of them … who has the time & patience to deal with all the wrong info & advice that is posted here.
It is my understanding The key difference between K & KE with regards to Mixture Formation is the addition of the O2 Sensor/Closed loop lambda which is more about ensuring the exhaust gasses are the right temperature and composition for the PGM Substrate of the catalyst to eliminate as much NoX etc from the exhaust as possible than it is about forming the ideal mixture for good drive characteristics and not visa versa as often assumed.Bad or no answers from people who come to a forum for help, is a problem, of course. But a bigger problem is wrong info & advice posted by people who again may have picked it up on the internet and think it‘s correct. KE-Jetronic related YouTube videos that are studded with wrong info/advice are deemed professional in this forum … and no one (including “retired or not MB techs“) opposes.
There must be some really clever monkeys in Australia.
Unfortunately, my posts about the KE-Jetronic here at Benzworld are hardly understood either. Maybe native English speakers find my long, nested sentences (as normal in technical literature in German) too tiring to read.
In the 1980‘s, one of the involved Bosch engineers I cooperated with once said to me (clairvoyantly
“Die KE-Jetronic wird die am wenigsten verstandene Benzineinspritzung sein, egal wie viele Leute behaupten, Sie zu verstehen.“
(The KE-Jetronic will be the least understood gasoline injection system, no matter how many will claim to understand it)
H.D.
The addition of the HEA o the fuel distributor of course having a bigger impact on drive characteristics than the Lambda.
Have I got that right?
Right, with respective outcomes.
… Particularly in case of CIS-E engine issues the outcomes are usually very different.The technical understanding of the KE-Jetronic allows for very targeted diagnosis in no time, even in case of problems that are not caused by the fuel injection system. … The absence of this understanding often leads to months of guessing & trying & counterproductive fiddling around with adjustment screws & wasting money on unnecessary part replacements … often even without solving the problem.
I‘d like the K-Jetronic to be kept out of this KE-Jetronic thread, actually. For discussions about the differences between these two systems a separate thread would be more suitable. ... Requirements regarding exhaust emissions (in combination with a catayst) and reliability and a (in case of, even complete, failure of the E in "KE-Jetronic") best possible limp home mode, after the reliability problems that Mercedes experienced with the D-Jetronic, were the main reasons for the development of the Bosch KE-Jetronic. Mercedes was the initiator of and involved in its development.
Fair point, the differences between K & KE are HUGE and best kept to separate threads. I do however take issue with your statement that the KE is easier to diagnose that the K but each to their own!Right, with respective outcomes.
The technical understanding of the KE-Jetronic allows for very targeted diagnosis in no time, even in case of problems that are not caused by the fuel injection system. … The absence of this understanding often leads to months of guessing & trying & counterproductive fiddling around with adjustment screws & wasting money on unnecessary part replacements … often even without solving the problem.
I‘d like the K-Jetronic to be kept out of this KE-Jetronic thread, actually. For discussions about the differences between these two systems a separate thread would be more suitable. ... Requirements regarding exhaust emissions (in combination with a catayst) and reliability and a (in case of, even complete, failure of the E in "KE-Jetronic") best possible limp home mode, after the reliability problems that Mercedes experienced with the D-Jetronic, were the main reasons for the development of the Bosch KE-Jetronic. Mercedes was the initiator of and involved in its development.
Mind the deatails! … I did not compare diagnoses of these two injection systems. I said (without mentioning the K-Jetronic):
“The technical understanding of the KE-Jetronic allows for very targeted diagnosis in no time, even in case of problems that are not caused by the fuel injection system. … The absence of this understanding often leads to months of guessing & trying & counterproductive fiddling around with adjustment screws & wasting money on unnecessary part replacements … often even without solving the problem.“
The comparison referred to diagnoses with and without technical understanding of the KE-Jetronic.
H.D.
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