zusatzluftschieber Djetronic MB

Hi Kerim,

how quickly do you loose fuel pressure when you switch off engine? Sounds like you have a leaking injector.

CO for your car should be up to 2.5% @ idle-run of 750-800 rpm.

dear dr volker ,
thanks for answer and help.
I measure the fuel pressure from the fuel pipe next to the cold air injector. When I turned off the engine last week while the manometer was connected I waited 5-6 minutes. pressure remained constant at 2 bar. There was no drop. I hope I am measuring the system pressure from the right place. You said CO2 for your vehicle should be up to 2.5% at 750-800 rpm idling. Ok, but isn't there a lower limit for this? For example, is 1% CO suitable?
thanks .
best regards
kf

Hi Kerim,

if pressure remains at 2,0 bar when switching off, you are okay. Measuring by removing hose to cold start valve and inserting manometer there is okay.

Bosch has no lower limit for CO. I would use 2.5% .

thanks dear dr.volker
I think I will continue to investigate what is causing the problem. I think the problem is caused by the thermal timer, relay, and cold injector trio. I will focus on these 3 points.
how do i send the künefe to germany? )

Hi Kerim,

you currently have 20°C at Iskenderum. That means that cold start should not be a big issue even of your thermotime switch or cold start valve do no work.

Can you measure fuel pressure when car stands a few days and will not start? And can you please just start ignition without engine and just push down gas pedal. Do you hear injector ticker then?

hallo dr volker
ok. I will do it.and , I will write result.
thanks

guten abend dr.volker( for turkei )
After 3 days, I want to repeat what I need to do and be sure.
1) First of all, I will connect the manometer to the fuel pipe next to the cold injector.
2)I'll just turn on the ignition (I won't start the starter) should I just measure the pressure this way without touching the accelerator pedal?
Or should I measure the pressure by pressing the accelerator pedal? Or should I just turn on the ignition and measure the pressure, then press the pedal to measure the pressure a second time?
which?
thanks

Merhaba Kerim,

when you switch on ignition your fuel pump will start to run for 1-2 seconds. At least after doing that twice you should see 2 Bar without fast dropping now. Do not touch gas pedal or start engine yet. Switch ignition off and watch for 20 minutes how pressure drops.

Now switch ignition on again and press down gas pedal and listen to enigne. You should hear that injectors ticker while moving gas pedal down.

Never leave ignition on for too long without starting engine. That might kill ignition coil, power resistors, ignition module. If you need to do so, remove pin 15 from ignition coil.

hi dr.volker,
thanks ,
I will do to morrow. Last Thursday, it worked hard with an additional battery. I will share this stage with you with a photo.
best regards

good morning dr. volker,
 As you said, I measured the fuel pressure of the car that has not been running for 3 days. it is 2 bar.
I am sharing pictures with you. The first picture is 2 bars.
I waited 20 minutes in the ignition off position.
The pressure remained at 1.9 bar. (second picture)
Then I turned on the ignition. I pressed the gas pedal all the way down. I heard "Clicks" sounds on the throttle stick. I'm not sure if these sound injectors?I tried to start the car. I cranked it 2 times, but it didn't work. The battery got weak. Then, after I gave additional charge to the battery from my other vehicle, the vehicle started at the first cranking. When I turn the vehicle off and start it again after 10 minutes of running, the vehicle starts quickly at half-start. The problem is only if the vehicle waits for 2 days or more without working, it does not work during the first start...
thanks
kerim

Hi Kerim,

but that sounds like an old and weak battery. It is charged when engine runs and it brakes down if not charged. How much is battery voltage after you tried to start once and engine failed? A good battery delivers 12,3 V .

hi dr. volker
I don't know about it. But I can do something like this. After waiting 3 days, I will try to start the vehicle with an additional charge to the battery from the other vehicle before starting it. If the engine starts at the first start, the battery is faulty. how do you think ?
best regards.

Hi Kerim,

why do you not just hook up a Multimeter and check. Then you know your battery voltage. Or you just install the battery of a properly running car.

good morning dear dr. volker
I measured battery shop. They checked it.
After turning off the engine, the battery drops below 10 volts (9.7V). They said it was faulty. I will replace it. I am using varta 74 amp. Is it enough? What is the ideal of this? secondly, when I checked the spark plug cable, it says Beru ZLE 121 on the cable. When I looked at your technical information list, I saw that it was Beru ZEF 470 or ZEF 473. Is this a significant problem? Does it make a significant difference?
(my car 1976 w114 280E)
thanks
best regards.

Hi Kerim,

please check your owners manual for the correct size of your battery. ZLE 121 is the model of spark ßlug connector. What I mention is the Beru set of all ignition cables together.

thanks dr.volker , I will look it.
I came new question )
In my vehicle, there is a black-capped druckfühler, which is type 3.
First of all, what should its mounting position be? Should it sit upright on the fender? Or should the black cover be mounted horizontally towards the headlights?
second question; I bought this part from ebay. I don't know if it is set up correctly. Is there any practical way to test this? Or how can I set it correctly?
thanks best regards

Hi Kerim,

best is if black cap is orthogonal to driving direction in horizontal position. And do not touch you MAP sensor. It does not detune by itself.

hi dr. volker
thanks for answer. I sent photo mail attach. this is false posision .( only type3)
ok?
thanks

Hi Kerim,

this is original position in W114. They had no space to turn it 90°. It qould be optimal to turn it. Worst position is to habe black cap upwards or downwards. Every bump on the street will cause change of MAP sensor. So it is better to have it horizontally. In your cars position it means that acceleration and braking will influence MAP sensor. If has black cap pointing to middle of engine compartment neither bumps on road nor braking will influende MAP sensor. Only if you are a very fast rider of curves. My 450 SL has this optimum position.

good morning dear dr.volker,
Thank you for your help. I am learning a lot and rediscovering thanks to you. I need answers to the following questions to adjust the throttle switch closed position;
first, for the 12/47/17 setting,
Will the vehicle's ignition switch be in the on or off position?
DKS I'm just going to remove the electrical socket. I will measure with a multimeter in the position where it is just by loosening the screws. (is it correct ?)
According to what I read in your article, you mentioned full path setting (full throttle position). Do I need to adjust this too? If so, could you briefly tell me how I should set it up?
After adjusting the idle idle shutdown, do I need to adjust this before tightening the screws and then tighten the screws. I'm confused about this. As a result, there are 2 different settings.
While doing all this, is the ignition on or off?
thanks for all
best regards
kf