Mercedes KE-Jetronic - Potentiometer calibration and replacement

[@Mitutumuch]

dude thanks for recognizing your awkwardness and embracing it lbro. You truly do offer actual learning and teachings here.

[@livin4today132]

Thanks, really enjoy your videos, very good for learning, how do you know if your potentiometer is bad , or starting to go bad?,

[@mercedeske]

Hi and glad you like the video. The symptoms-The car won't idle as it should, as you start the car in the morning it dies shortly afterwards...

[@charlestimmis273]

In another Video. The technician said to remove the ECU plug and put the car in emergency mode before doing this? any idea why?

[@mercedeske]

Absolutely no need! Just calibrate the potentiometer the way I described it and there is nothing to worry about! Happy Mercedesing!

[@roooomaa]

Hi mate. Thanks for your great videos. I was wondering if you can give me some ideas. I have 1982 280SE. It work fine on idle but when you put into the gear rev goes down and engine stalls then car stops. What would be the potential reason for it ? Thanks a lot

[@mercedeske]

Hi, mate. Bad ICV. If you put in D and the car stalls, take off your ICV(the Idle control valve) and clean it first for couple of hours in diesel and then clean it again with carb cleaner and either use q-tips or let it dry by itself. Always keep it laying upside down( in an L letter shape 😀). Afterwards mount it back in the car. Happy Mercedesing 😃

[@andrewshafik1158]

Hey I like your videos about the KE. I have a question about the symptoms of a bad potentiometer. My 190e 2.0 has a bad cold start and when it gets fired up it keeps dying or hesitating if I try pressing the gas pedal (between 1000-2000 rpms). I have no air leaks, changed my fuel pump, 4 pin coolant sensor, I adjusted my mixture using a CO gauge. Also my acceleration at the high rpm range is not good.

[@mercedeske]

Hi! Thanks. That is a bad potentiometer. This is how you check it out - measure the resistance between the contacts 1&2 (from the top to the bottom) if you don't get the resistance 3.6-4.4 kiloohms then your potentiometer is bad. Generally if you start your car and it dies after a while then it's about the potentiometer(as the car has to maintain idle).

[@andrewshafik1158]

Thank you i will try and let you know

[@michelgroen1982]

Hey again, thanks for this video. My current LMM is reading out the following measurements. Valve closed pin 1 en 2 2,5k ohm and pin 2 en 3 7k ohm. Valve fully opened 3,2k ohm. So I guess my pot meter is broken. If I replace is and place it at the exact same position, will this still work or do I need to calibrate the replacement?

[@mercedeske]

Hi and thanks for the comment. You will need to calibrate it. It's just a matter of patience and precision. I saw on ebay someone in the Netherlands selling potenciometers. There are some people in Germany. You will get full instructions how it's done. I bought it from the man from Darmstadt. If your car has more than 150k miles on the clock then this can become an issue.

[@michelgroen1982]

@@mercedeske Thanks, I ordered one. Will replace it myself, but as many different people have been changing the CO screw and such I a bit unsure if I can easily calibrate it. Will see how it goes :)

[@mercedeske]

@@michelgroen1982 The CO screw determines the starting position of the plunger. It's important just that the plunger doesn't touch the sensor plate. That's why it has to have a bit of a gap and that's in ideal case 1.9mm as they say. You can hook the multimeter if it can measure % and you have to get the fluctuation 45-55% once you adjust the co screw according to the multimeter that's its ideal position.

[@johnnybravo6672]

Congratulation for your first 1000 subscribers! Do you have the needed hours for the monetization?

[@mercedeske]

Yes, I do. Thanks for your wishes, stay safe and "Happy Mercedesing"💪💪💪🍀🍀🍀😎😎😎

[@Heve62]

what are the symptoms of not calibrated potentiometer? i changed the intake air temp sensor and now the car runs 1300-1500rpm and has hesitation on whole rpm range? and the potentiometer showed 1.08V and 1.3V took the measurement twice, difference due to engine at different temperature probably. the potentiometer was changed and tuned with the faulty temp sensor so can it now be out of tune?

[@mercedeske]

Too much, calibrate it at 0.7V. The symptoms are bad or high idle, stalling engine, jerking. 1V is too much. Recalibrate the potentiometer

[@Heve62]

@@mercedeske does the potentiometer have any effect when the car is warm? read online it only enriches the mixture when engine is cold or warming up

[@johnnybravo6672]

Great video once again! Just keep going like that!

[@mercedeske]

Thanks! Will do!

[@bogdan-gabrielbiciusca5588]

Hello! I have some problems with my w124 230e 1990. The idle is not stable. Otherwise the car when is running is ok. But when I have to stop, some times the idle is not stable is fluctuatin between 800 rpm and 1200 rpm, the engine is shaking. Also when I press the cluch pedal the idle is not stable. Sime times when I start the car, after starting the car turn off. Can you give me sime advice what to check? I changed the fuel pump, fuel filter, engin oil, oil filter, plugs, plugs coil, cover of coil, gnertator of coil, ovp sensor, and potentiometer sensor.

[@mercedeske]

Hello, have you replaced the injectors? When the engine turn off, when cold or warm? That's a huge difference!

[@bogdan-gabrielbiciusca5588]

@@mercedeske hello! The engine is turn off imediatly after I started it. Like it is trying to keep the idle, the rpm is going to 1000 rpm and suddenly drop down to 600 rpm and the engine stop. But this thing is happening from time to time not always. The idle is not stable always from 800 rpm to 1000 rpm and engine is shaking when the car is running but is not moving, and when I push the clunch pedal. I didn’t check the injectors because the car is running ok when is moving, no smoke, the acceleration is ok and the engine is smoth. I found some problems that you described in your videos: 1. The potenstiometer of the air sensor is not reaching the value between 3.6-4.4 kohm.(when is mounted on the ke-jettronic the maximum value between pin 1 and 3 is 1.95 kohm)… and the car seems that is not changing the behavior when I cnnect/disconnect the jack. 2. The second thing is that the ke-jetronic is setted at value of 3.5 mm. If i’m trying to approach the value of 3 mm the engine is stopped. 3. The jack of the air flow sensor (maf) is disconnected and the same like for potentiometer, if I connect it or disconnect the car has the same running. 4. I found in trunk from old owner the ovp relay. It’s is from vemo but with 9 pins and 2 fuses. The one that is on the car is the original one with 8 pins and 1 fuse. When I mounted on the car, it was ok, just abs light turn on, because one fuse had poor connection. After I changed the fuse the car running like before with old ovp relay and abs lamp turned off.

[@bogdan-gabrielbiciusca5588]

Today, I tried to make some ajustments of potentiometer to get 0.7v and of co screw. I made it, but after all of this still I didn’t get the ideal 1.9mm of free movement of ke-jetronik. To have the smoothest engine running, I ajusted it around 3.15 mm. I measured also the ehv how you described in your video and seems to be with right specs. In the end I will atach a link of the video with engine running; it seems like when I press the cluch pedal some times the idle is fluctuating, the same when spinning the steering wheel. The start of the engine is the same when is hot or when is cold, but not the best, I mean the engine is turning 6-8 times before starting. On the other hand at the exhaust pipe you can hear some sounds like bubbles and I suppose that means the mixture of the air with gasoline is not the correct one. What do you think? Can you please give me some advice ? Thank you in advance. we.tl/t-JjMJZuwAHz

[@bogdan-gabrielbiciusca5588]

In this video you can see how the engine is starting. At the beginning after engine start it had a drop of rpm util it is stable. And after that again when I press gas pedal the rpm falls and fluctuating a bit until is stable again. What do you think? After that always when I press gas pedal the engine is stable! Thank you! we.tl/t-vPbIp3jTYE

[@mercedeske]

Hello. I watched the video. There is some strange sound when you press the clutch but that's not related to the system, there you should check the thrust bearing. Concerning the rpm fluctuation, if you make a full turn, from lock to lock and there is a drop in rpm, then check the icv{the idle control valve). Concerning the mixture adjustment, you will have to provide me with the type of your engine(just tell me the year and how many liters is your engine).

[@robertrichardson1779]

Can I ask, what is the relevance of the voltage on pin 2? My car runs well but is at 1.2v on pin 2 at idle? What does lowering it to 0.7v affect?

[@mercedeske]

This is the voltage it has to be on idle, that's how the manufacturer requests. The pin 2 is the signal that the potentiometer sends to the ecu. The pin 3 is the signal from the ecu to the potentiometer.

[@oceanfront664]

-hi, thank you for a great video! I just want to confirm the calibration process- mm on volts and potentiometer plug pulled out a bit and mm leads on pin 1 and 2 until you achieve 0.7v +/- 0.1v correct? thank you!

[@mercedeske]

Yes, correct! :D

[@oceanfront664]

Greetings, o.k. i finally got around to changing my potentiometer...upon examining it had scratch mark, like yours! Once, I put on new pot. I used, pin 2 as positive, and used, a screw for ground. In your video, you use first pin as positive?? Did, I use wrong pin for positive? I got 1.2 v With idle dropping all the way to bottom, and swinging, back up! If i lowered, the right side, it idled very fast!! The, left side of pot. You, can not move up, as, niple inside will only allow, a tiny bit...So, I tried just moving right side, which has more room for movement... But, could not stop the idle from fluctuating up and down in close loop. My dear, sir, what I'm I doing wrong?? Please, help! Advice Thank you!!

[@mercedeske]

Use pin 1 as negative and pin 2 as positive. After each movement wait for about 10 seconds for the ecu to understand that there is a change. Be very patient and do it very very precisely.

[@mercedeske]

kzbin.info/www/bejne/d3nOmYlpectsf9E Watch this video and do it as I say.

[@oceanfront664]

@@mercedeske just an update...when, I do a resistance test on my (new pot). I only get 1.7 kilohms. Bad, pot??

[@r3FMusic]

Yeah. Your video timing is perfect. Everything is understandable. The TPS number I have is "3 437 224 024" but I couldn't find the same. Provide a compatible model number. M102.963 200E non-catalytic model

[@r3FMusic]

Sorry.. u said it's okay for the idle speed to go up to 2000 each time. But I suspect .. kzbin.info/www/bejne/qWiWpJ5rmLF8hdE

[@mercedeske]

This is how it is. The one I bought from Germany is compatible with 200E 1986-1992 although it doesn't say that there is the number of your potentiometer. From what I found concerning one like yours I wouldn't recommend you buying used stuff. As for the label of your engine mine is also m102 963(962, 963,982,985). It's up to you to decide if you want the new one from Germany from the man that makes only potentiometers(38.50€ plus 4.80€ shipment). How ever you decide.

[@r3FMusic]

I can buy quality products. Where can I find the purchase address? I don't want those sold in the market made in China

[@mercedeske]

This one is from Germany, Darmstadt, 5 years warranty. Here's the link and you decide if you want to buy it. www.ebay.com/itm/Drosselklappensensor-MB-Mercedes-Benz-03437224015-03437010039-03437224035/133173658800

[@r3FMusic]

Thanks again. i grateful.

[@Pellogt]

Hi mister. I don't know if you can help me. My w124 has a problem with the radio and hazzard. When I open the door start working again( the two door switch , the second one is the one when you released start working the radio) I don't know where to start... Because the other door (passenger ) does the same.

[@mercedeske]

If you can find a good electrician. I can't tell about that. Maybe the hazards are connected to the light as you open the door... Something is connected wrong I would say.

[@Pellogt]

@@mercedeske I'll check. Suddenly happens the other day... Open the door and start working again. I need to know where it goes the door switch

[@mohamedamer8833]

I believe I don't have this part in my engine, my engine is M111. Is it available in M111 series?

[@mercedeske]

No, you don't.

[@oceanfront664]

Greetings! I ordered a new bosch pot. From an online site. The pot. Very expensive, and picture shows pot. As green/orange, but, when my pot arrived, it is black! Even though it came in a bosch box. If, it is black does it mean it might be a chinese brand? Also, it came with a rubber gasket...I noticed your replacement did not have a rubber gasket...how important is this rubber gasket? How to tell when a pot. Is oem, or oe? And not some imitation in a bosch box? Please, advice-comment. Thank you, sir!!

[@mercedeske]

Yes, I also received that gasket but the old one is still doing business so I didn't want to replace it. Concerning the potentiometer I don't think it's a Chinese copy, I read somewhere it says BLACK EDITION. If you bought the original it must say somewhere MADE IN GERMANY 🇩🇪. I can say nothing until I see the box.

[@nunoalmeida1977]

Hi! Thanks you for your great vídeos. My 190E 1.8 accelerates with bumps and hesitations until it gets warm. After it gets to 80-90°C it runs much better and smooth. It starts easily when cold. After gets warm the start its harder but drives better. With full throtle it goes ok (cold ir warm). What could bem the problem? Thanks you very much.

[@mercedeske]

Hi. Check your potentiometer, I have already got an answer from the subscriber that he bought a new potentiometer but he didn't calibrate it to 0.7V. So you check it also.

[@mykcarrestoration3965]

hye sir, can u do a tutorial on how to repair the fuel economy gauge not working? thanks

[@mercedeske]

If it's not working then it can be up to the connection. You will have to remove the dash and to see in which condition your tube is.

[@lebojay]

At 1:39 we can see the two metal wipers inside the air flow metering unit that touch the potentiometer. What can I do if one of these wipers is broken off?

[@mercedeske]

You would have ro replace the whole airflow unit but with the corresponding one. Watch this video about the corresponding airflow meter. kzbin.info/www/bejne/bXSTmnSig5aNn6c

[@oceanfront664]

Dear Sir, would you comment on how you went about tightening the screws on pot. I tried to install new bosch pot. But, everytime i had it set at 0.70, and then tighten, upper right screw first, I ended up with 5.2, seems everytime I try to tighten that upper rt. Screw the pot. Signal drops, so it must be moving down as i screw in first screw... Today, I was at it for 4 hours!! So, I changed to tightening, bottom right once i got 0.70v and tightened in cris cross pattern, but still ended up with 5+v...? What I'm I doing wrong? Do, you have a method, or is it just trial and error... Last pot. I did it on second try! Would you please comment on how you did it? Any words, of encouragement? Thank you, very much!! Indebted to you!!! P.s. once i have, the calibration to 0.70 I turn engine off, and begin to tighten...

[@mercedeske]

Don't turn the engine off, you must do that while the engine is ON!!!

[@oceanfront664]

@@mercedeske thank you for your reply, on my 92, 300e i have to turn engine off to remove fuel pressure regulator as it is blocking right bottom screw...unless you use a special tool to fit without moving f/p regulator? thank you!!

[@mercedeske]

@@oceanfront664 Of course. And as you replace the potentiometer get everything back and then start the calibration

[@oceanfront664]

@@mercedeske o.k., will look for right torx tool that will make process easier... thank you!!

[@jojbernard]

How to remove without a screw? One doesn't have screw..thanks.

[@mercedeske]

You mean the potentiometer?

[@jojbernard]

Yes... Some doesn't have screw...

[@jojbernard]

I have a 190e 2.3 8 valve..when I started and change gear the engine turned off and black smoke came out from the exhaust...do I have to adjust the potentiometer or the fuel distributor? Thanks ,hope you have time to share some knowledge..

[@mercedeske]

@@jojbernard Adjust the potentiometer if you haven't done that and afterwards the mixture at the end. Potentiometer and lambda are precondition for mixture adjustment!

[@jojbernard]

@@mercedeske thank you..

[@Ozkan_Ozturk]

may be a stupid question because you showed how to easily change the Potentiometer but have you ever seen a situation where the whole assembly, that you are holding in your hand, needs to be changed just because of this little 3 pin plug? does this potentiometer cause hard start issue 30+ minutes after when the engine is still hot (provided that other components are ok) ?

[@mercedeske]

Let me tell you how it goes - the whole unit has nothing to do with the potentiometer. The mechanics at the dealership don't know how to calibrate the potentiometer but as you give them your registration and they see the VIN of your car, they send it to Bosch and Bosch then makes the whole unit and calibrates the potentiometer for them. They get everything back and you pay 600euros for loosening and tightening screws. As for the potentiometer - it fine tunes the position of the sensor plate. As the graphite is worn the metal scratches metal and ecu doesn't know what to do and erratic operations occur. It has nothing to do whether the car is cold or warm, the car tends to stall as soon as you let your foot of the accelerator. P.S. If you donate me again any money I am going to make you a scheme in which direction to go how to understand the system, even more simple made!

[@rudynuryanto5280]

hi sir, i have a problem with my mercedes 300GE. i have change the injector valve, but the fuel that coming out from injector valve is not as it should be. and it also causing high fuel consumption. i need some help from someone with a lot of experience like you. if you dont mind, can i have your contact? thank you

[@mercedeske]

Contact me on my facebook page. facebook.com/mercedeskejetronic

[@rudynuryanto5280]

@@mercedeske i have sent you a message on FB

[@Rossithailand]

Thanks for help and advice

[@mercedeske]

My pleasure. Happy Mercedesing 😃

[@patricksousa183]

hello, thanks for your videos, I'm sure it makes a lot of people happy. I have a 190E 2.3. the problem is when I start it for the first time (Cold start) it doesn't hold on. To keep the car running I have to accelerate for 2/3 minutes until it warms up and then I just stop accelerating and it holds there. after that, if you turn it on again, it will hold because the car is already hot. what can i do to diagnose the problem? (I tested the potentiometer on pin 1 and 3 with the resistance of 4.20, on pin 1 and 2 the resistance is about 9) (connected with it hot 80 degrees I get a value of approx 0.9 v / )

[@mercedeske]

Hello and thanks for your nice words. For the beginning try to calibrate the potentiometer to 0.7V. If you don't succeed, replace it or test it. You must have an even increase in resistance and then at the last third the resistance has to fall. If it doesn't happen replace the potentiometer.

[@marcusfinanger1116]

My 260e has a surging idle after start up it goes to 1700rmp then drops to 300rmp and does this in cycles. Also sudden acceleration and brake when slow speed in drive.. Just started doing this suddenly and now it won't go away

[@mercedeske]

Replace the potentiometer if you haven't.

[@marcusfinanger1116]

@@mercedeske ill try that

[@Fkzionism]

"And that's it" 😆

[@mercedeske]

Happy Mercedesing 😃 🍀😃

[@ayhan8137]

Pozdrav, problem sa ler gasom, 1500rpm. Nije bitno hladan ili vruć isti problem. Potentiometer 0.68v Icv ispravan..kada ga izkljucim oko 1000rpm Ovp osigurac ok.. ovp izvadjen radi na 800/1000rpm Predlog? Hvala unaprijed W124 200e 91

[@mercedeske]

Pozdrav. A tps, jel ispravan? Motorić sa mikroprekidačem? Jel ga pipa poluga gasa, jel ispravan?

[@ayhan8137]

@@mercedeske da pipa ga, izmeren na zvuk signal i radi prekidač

[@mercedeske]

@@ayhan8137 Fals vazduh?

[@ayhan8137]

@@mercedeske što sam mogao vidjet nema, preostalo je dim test

[@mercedeske]

@@ayhan8137 Sto se tice step motora(icv), provera kaze da se upale kola i ako posle izvesnog vremena hladan ne spusti obrtaje na 800 onda icv nije u redu. Isto tako ako spusti, a kada okrenes "pun" na levo ili na desno, auto se ugasi(kod automatika kada se ubaci u D). Tada ne valja icv. POstoji jos jedna provera - povuces rucnu, ubacis u prvu, ne dodajes gas i polako otpustas kvacilo. Kada padnu obrtaji na skoro 500 ti opet skisnes kvacilo. U tom slucaju obrtaji treba da skoce na 1500 pa da padnu na 800. Za ler gas su zaduzeni icv, ako on dobar onda falsira negde. Imam klip na kanalu gde sam postavio vrednosti koje treba da ispuni icv(naon, otpor i amperaza) kzbin.info/www/bejne/oKmbqYqjdrGgfc0 Gledaj od 15-og minuta.

[@carlosramirez-vt3vc]

Que bueno sería en español para entenderlo mejor saludos

[@tiberiusmartin4620]

hello ivica because my mercedes 190e 2.0 runs drowned

[@mercedeske]

How come "drowned"? Is the mixture too rich?

[@tiberiusmartin4620]

problema resuelto una pregunta mas porque cuesta arancar en frio gracias@@mercedeske

[@mercedeske]

Entonces, no más problemas, ¿verdad?

[@tiberiusmartin4620]

@@mercedeske buna ivica como puedo verificar la valvula de arranque en frio me cuesta arrancar porlamañana gracias

[@golfrat420ratlook7]

legends please

[@mercedeske]

I didn't understand that. What did you want to say?

[@hostalesdebuenosaires]

Alto violeta sos...