Great and congratulations! Feel free to ask if something is not clear or seems to be missing!

Thank You!

You have to remove the fuel pressure regulator then adjust the pot, tighten the screws but not fully tight so you can install the pressure reg to turn on the car and adjust the pot. Once set you have to remove the regulator to tighten down the pot screws

CC doesn't work - KZfaq is suppose to automatically add those

Excuse me I didn't know. Subtitles are now open. I'm sure the best tutorial video for adjusting my throttle, you made it. I am grateful.

Check the fuse(s) in the OVP Relay

Ovp fuse is good

The high idle issue is solely between Idle Speed Control Valve, Idle Speed Control Unit - Operating Voltage for those is supplied by OVP Relay The Potentiometer you adjusted supplies feedback only to ecu for emissions control / fuel mixture - has nothing to do with idle

@@thomasbuerkle2141 then you need to check your ICV and Idle Speed Control Unit

@@thomasbuerkle2141 if both ICV and ISCU checkout ok then you have a massive vacuum leak - check brake booster and brake booster vacuum hose and all other vacuum lines connected to rear right side of upper intake manifold

Hi Roy, This is pretty much detailed in the groups which deal with the EzL and Ecu. A learning mode may not be the exact term especially not when compared to today’s standard. The ecu has a RAM chip and the microcontroller stores constantly certain values to RAM, like RPM, coolant temp etc. It takes 40 starts plus driving several miles to fill this memory back up which is then used during starting and driving as database for comparison and to calculate average mean values. This memory can be erased by two methods: 1. Full reset after last error was reset by moving ignition key to off before 10 seconds after reset. 2. By disconnecting the negative lead of the battery for more then 10 seconds All this data does is to smoothen out operations and works after the FIFO principal. First in First out - so data is rewritten every time you drive

@@inovahightechltd I most highly appreciate your reply, thank you. Will have a closer look at your videos.

Hi Roy, Please keep in mind that this is documented in the Manuals with model change in 1986 Sincerely, Petet

@@inovahightechltd Thank you, Peter. I have the manuals applicable to W126 with V8. Which section do you recommend? I am assuming you are referring to one or more that would be in group 07.3 (Mechanical-Electronic Gasoline Injection). I am genuinely interested and would like to read more on this subject; I have two 126 models, both with V8. Thank you again, Roy

Roy, I have to look through my manuals. I have different versions between English and German. I believe it was in the addendum for 86 model change or a service bulletin. I will report back to once I find it but that may take a couple of days until I get to it. Sincerely Peter

Fairly smooth, you may need to lean the mixture out a bit more. Was the fuel Distributor rebuilt as well? The engine will be idling rough if the mixture is to rich or to lean - if the old potentiometer is bad then the ecu will run the engine rich as it opens the EHA valve fully - its like a limb mode - I would wait until I get the new potentiometer before making any further adjustments. The Hirschmann clamps have to be connected with the harness connector at the same time. Pull connector off, attach the clamps from the side on the pins as close as possible to the potentiometer and then push connector on and as far as it will go against the clamps to make sure you have a good contact

And the other question, have you opened the camshaft cover and checked the marks for tdc on balancer, camshaft and distributor? They all three have to line up as well

You may want to watch this video here: kzfaq.info/get/bejne/hN51jKxisK-5lXk.html

@@inovahightechltd I will watch it and check the other things while I wait for the new potentiometer. Thanks very much!

@@thomasbuerkle2141 black smoke is usually a indicator of to much fuel. If you haven’t rebuilt your fuel distributor then you may want to check if your fuel distributor is leaking: 1. Remove fuel pump relay and bridge contact to activate the fuel pump check your wiring diagram for ur car to see which two contacts need to be jumped. 2. Open each fuel line on the fuel injector one by one - there should be no fuel coming out except of what was in the fuel line already 3. If you got fuel flowing out of any one or two lines then your distributor needs to rebuild 4. If you got fuel flowing out of every line then your plate is adjusted to high - turn mixture screw counter clockwise until fuel flow stops on all six cylinders 5. At this point turn set screw another quarter turn counter clockwise, remove jumper, re insert fuel pump relay and start car normally - this first start will be rough to start and you may have to crank for up to 60 seconds until all air has come out of the system - once engine fires step on gas and rev up to 4000 rpm to bleed fuel system completely for about 15 seconds After those type of fuel repairs there is a good chance too that the cylinders are flooded - once engine starts accelerate engine to 2000 rpm and if it was flooded the excess fuel will burn off within a few seconds to a couple of minutes - expect plenty of smoke - let engine reach operating temperature and let it idle for 5 to 10 minutes then shut engine off

That I am not sure. Check with the MB Service Manual Group 7.3 for your Model and Model Year! Peter

Should have

@@inovahightechltd will take a picture tomorrow

@@inovahightechltd do you have an email or something? I can post links to imgs here apparently. Thanks!

@@SiMan-46 peapvp@gmail.com

Christian, You may want to watch this video too. Then the hole thing may make more sense! Thanks for watching! kzfaq.info/get/bejne/j7NkiaeKxrHIdoE.html

Hi Richie, if you have a V8 3.8 4.2 5 or 5.6 Liter engine then you may want to watch this video here to answer your question since it really depends on what your current position for the stop and resting position is: kzfaq.info/get/bejne/fZNkfNZinq6ZhIU.html

No, that’s correct You can adjust the plate first and then adjust potentiometer and see what difference this makes

@@inovahightechltd thank you for your answer and all instructive video

Hi Charles, No

Yes it does - the fuel pump relay gets the ambient / coolant temperature from B12/2 I think it is (2 pin or 4 pin)

Thanks !

Hi Fabi, genuinely it should not be a big problem. The quiescent current with 4.2K is 1.2 mA and with 1.7K is 2.9 mA. The question is, can you adjust the pot to 0.75V between top and middle pin when engine is at correct idle speed?

@@inovahightechltd Thanks for your quick response. I bought it as a reserve spare, just in case. Hope it will be ok if needed.

@@fabit.8734 Hi Fabi, I looked further into this question yesterday and investigated the input parts used in the ECU’s. I have several here for 103, 116 and 117 and all use the same input circuit for pin #17 (wiper from poti). Those are two 1% metal film 1/8W resistor in series between 5V and Ground . Those are R300 10KOhm and R313 510KOhm. The connection between both is pin 17. This divider network will have 4.96V on pin 17 with poti disconnected which the ecu recognizes as error and turns on engine check light. With the Bosch Poti 4.2K the voltage on pin 17 will go from 0 to 2.5 V with 0.75 V set as idle reference and Throttle switch closed in idle position. With the 1.7K potentiometer the voltage range will be reduced to 0V to app 2.1V which means the engine is going to run richer but may experience substantial acceleration problems in warmup phase between 45C to 75C coolant temp. I soldered in a parallel 5.36 KOhm to R313 510 KOhm in my ECU which limits the Voltage range now on pin 17 from 0V to 1.7V which eliminates the warmup acceleration/power issue but also may limit the highest attainable rpm from 6000 to around 4500rpm over all - I need to verify this fact with possibly reduced max rpm in more detail in the next few days. We got a snowstorm here today and have 1/4” of ice below the snow. Thanks again for pointing this out. I will make a video on this issue and would like to know if I can mention your name in the video. Sincerely Petet

Yes, but I believe on the Porsche / VW the plate action is in the opposite direction from the MB system, meaning plate moves up, not down. Otherwise everything is the same

@@inovahightechltd Thanks! You make what was a mysterious fuel system simple! My problem is I messed with the 3mm Allen and that was that! So I want to bring it back to a baseline so it starts...

Craig, just follow the video(s) it takes patience but once you get the hang of it then it’s a piece of cake! Just remember, plate adjustment with Allen key only with a running fuel pump (jumper the fpr) otherwise you will loose your hair! Peter

4.7V to 5.2V

@@inovahightechltd 🙏🏻🙏🏻🙏🏻thank you very much

Remove your fuel pump relay and bridge contact 7 and 8 with a jumper. This way you got fuel pressure in distributor. Don’t start the car yet. Push down on your plate until you can hear fuel flowing. Your plate should be only about 2mm below resting point with fuel pressure. If you can push the plate in below this then your to lean - if the plate has a lot of resistance then your to rich - you need 2mm play between resting and fuel flow

That’s the basic alignment

And make sure the Allen screw which is spring loaded releases the set screw below - they can get stuck when Allen key is depressed then the plate doesn’t reach the fuel distributor plunger and you get no fuel flow

Then your car should start / leave fuel pump jumped for the moment - if it doesn’t start turn 1/8 ccw to lean this way the vacuum has less resistance to move plate down - but be careful these adjustments shout only be made I. 1/16 or 1/8 increment turns in either direction

Your rpm gauge should go up to 1200 to 1600 rpm and then drop off to idle between 5 to 45 seconds depending upon ambient temperature

Hi Alex, This points to a failing fuel distributor. Time to get a rebuilt one. The O2 is irrelevant during start / warm up. It comes into play when the engine has warmed up and goes from open loop to closed loop control by the ECU.

@@inovahightechltd Will try that, thanks

Today I checked the resistance on the potentiometer between 1and3 pins with no connection and shows 0

Time to replace it. Not sure if you saw all the other videos I made of testing those and all the other parts. The potentiometer is only used for the EHA valve control to adjust mixture. When cold, the engine runs pretty rich until at operating temperature. The engine will start and run without the ECU and EHA valve operational - this is called the limb mode and indicated by the illuminated check engine light.

@@inovahightechltd Hello, thanks, I have seen several of your videos , there is a parts store that has the potentiometer in $28 I don’t know if is good has good reviews. I opened my bad potentiometer and found a 3006P-1-201 which costs $3.23 inside , seems to be fair easy to replace and resoldering in place

Hola David, ¡gracias por tu comentario! No hablo español y estoy usando el traductor de Google para escribir esta respuesta. No puedo copiar su comentario en el traductor de Google, así que le pediré a mi amigo Martin que me lo traduzca y luego responderemos a su pregunta. Pedro

@@inovahightechltd Gracias por responder, un abrazo!!!

This will take sie some serious troubleshooting. My recommendation would be to watch all my videos as they relate to fuel issues