Motor läuft nicht?

Merhaba Juan,

a totally over-rich mixture is normally caused by

1. Too high fuel pressure
2. Broken diaphragm on type 2 MAP sensors or detuned type 3 MAP sensors
3. Engine temperature sensor giving wrong resistance or broken cable

Whenever I return to İstanbul, I will take some time to see your car. But unfortunately no plans yet, at least not in winter. Turkey did very seldom import luxury cars like your SL. That is why Turkish mechanics normally do not have experience nor tools to maintain and troubleshoot such a D-Jetronic car. What you find in Turkey are W114, W115, W123, W124 and W201. I was amazed last year to see so many W124 still running in Antakya. And I always see Stroke8 and W123 still running around Izmir as daily drivers.

Meaning: You should forgive your mechanic that he can hardly have any knowledge of D-Jetronic.

Hallo Volker,
Entschuldigung das ich mich hier einmische. Wenn ich die Texte richtig verfolgt habe wird der Sprit immer für zwei Zyl. in das Saugrohr eingespritzt.
Funktioniert jetzt ein EV nicht, reicht auch die Spritmenge nicht für die Zündung des zweiten Zylinder. Oder ist das Saugrohr unterteilt ?
Oder ist dies eine dumme Frage ?
Hans-Jürgen

Hi Juan,
you already posted some resistance and voltage readings - but you didn't post the resistances of the temp sensors.

Those are essential, <as Volker wrote before> when the engine dies running rich after the first warmup.

Please read pin 23 <blue-white>: coolant temp sensor (NTC2) = temp. sensor II against Pin 11 (ground)
0° C 32° F 5,9 kOhm
20° C 68° F 2,5 kOhm
40° C 104° F 1,2 kOhm
60° C 140° F 600 Ohm
80° C 176° F 325 Ohm
100° C 212° F 190 Ohm

and pin 1 <blue>: connector air temp. sensor (NTC1) = temp. sensor I against Pin.11 (ground)
-10° C 14° F 960 Ohm
0° C 32 ° F 640 Ohm
10° C 50° F 435 Ohm
20° C 68° F 300 Ohm
30° C 86° F 210 Ohm
40° C 104° F 150 Ohm

Please do the readings dicectly at the ECU-connector. I'm quite sure you will find the reason for the problems...

Regards
Norbert

@Hans-Jürgen: Die Einspritzventile spritzen direkt vor die Einlassventile des jeweiligen Zylinders. Fällt eins aus, betrifft es also ausschließlich diesen Zylinder.
Und: Der Einspritzzeitpunkt ist ziemlich unwichtig. Dies ist keine Direkteinspritzung. Falsche Einspritzzeitpunkte z.B. durch vertauschte elektrische Ventilanschlüsse oder vertauschte Triggerkontaktleitungen wirken sich kaum aus. Man merkt es kaum an Leistung und Motorlauf, und der Kraftstoffverbrauch ist auch nicht massiv höher.

Hallo Volker,

Grüsse aus Istanbul.

Thank you for the technical advice.
1.Before the Map sensor was sent to Germany for retuning I had personally checked with the mechanic the fuel pressure again. it was 2.0 bars. I can have it checked again as he has the device and it is quite a simple procedure.
2. I suppose my Map sensor is of type 2 (0280100012) since the black screw type adjustment knob is not there. I received the unit quite recently from Bosch Service and I would like to believe that everything was thoroughly checked and the unit was retuned to the original specifications.
3. I have not checked the engine temperature sensor at all. I will ask the mechanic to do it.

Regarding the models available in Turkey you are almost right. My father owned one W124 in the past. As you said they are still in the traffic. I would say it is a quite reliable car. We still have many on the road in Istanbul, too. Even though you do not see many w116 - 280 S was a quite popular car in Turkey. The SE type which I assume came with the d-jet was also available.

As I undertand that the mechanic is not very much familiar with the basics of the operation I try to gather and feed all the info I can get to this gentleman in order to get the most out of him.

Again I would like to thank you as the moderator and to all contributors for the support you are providing.

If you ever visit Istanbul It would be a pleasure to welcome you here.

regards
Juan

Hi Norbert,

You are right I have not checked the values of the temperature sensors before.
First thing tomorrow will be to ask the mechanic to perform these readings.
If I am not mistaken the readings must be done on the ECU-box connector not on the engine.
The air intake temp. sensor was replaced few years back with a new one from MB.
Coolant temp sensor I have not touched before.

thanks again
Juan

Hi Juan,
yes - the readings must be done on the ECU-box connector.

The influence of the coolant temp sensor is much higher than that of the air temp sensor.

Missing air temp sensor makes the engine run richer - missing coolant temp sensor enriches the engine so much that it spottters and finally stalls when having warmed up.

Your mechanic can install simple resistors (1/4 Watt will do) of about 200 Ohms to simulate the sensors.

Regards

Norbert