CIS-E function of EHA and fuel distributor

I can't start my 1987 190E 2,3 (posted earlier).
Ignition and fuel pressure seems OK (strong spark and specified flow through pressure regulator), Voltage inputs to ECU are also OK.
Pressure at cold start valve output of fuel distributor seems OK, but the 4 injector outputs have very little pressure, i.e. fuel flows proportional to the posistion of the air mass sensor (from none to some milliliters per second). Applying 20 mA current through the EHA hans no (or at least not a noticable) influence on the flow rate.
Is it normal, that fuel to injectors are not under preasure, and that EHA current has such little effect?
Any suggestions?
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To read fuel pressure correctly, you need a special 2 hose gauge because you have to read upper and lower chamber pressure.
With the air cleaner off, what is the position of the sensor plate: Even with the opening? Or above the opening?
A common problem is a slight backfire that pushes the sensor plate up and bends the arm. Then when you crank the engine, engine vacuum pulls the plate down so it is even with the opening which cuts off air flow.
If you look at the air opening where the sensor plate sits, you will see it opens out at the top, then it goes in about the thickness of the sensor plate, then it opens out again. The plate has to rest evenly all the way around where the opening is tapered in. The plate should have slight freeplay when you touch it with the engine off.

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Thanks for responding, Karl
When engine is off, It is flush with the upper edge of the cylindrical portion (where the plate just fits in). There is a few millimeters of springloaded freeplay until it starts acting presumably on the control plunger of the fuel distributor.
When cranking the engine, it opens a few millimeters due to the airflow.
I believe this is about normal as you say (or?).
As you have also responded to earlier, I am trying to track down why it will not start. It does not ignite at all in the cylinders now, althoug spark is present as well as fuel supply (pressure to the fuel distributor).
But I am very much in doubt how the pressure at the injector outputs should appear. I would expect that there would be some pressure to be relieved when uncrewing an output with the fuel pump on (jumper at fuel pump relay), but i really doesn't appear that way.
Is that normal?
/Jens
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Re: Fuel from injector output with fuel pump bridged. No fuel should come out of the top of the fuel distributor UNTIL you press down on the air flow meter. Then fuel should flow in equal amounts from all injector outputs. Cranking the engine over has the same effect. Full fuel pressure is only achieved with the air flap pressed all the way in.

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Thanks a lot (sorry for late reaction, but I was occupied elsewhere the last couple of days).
It does react as you say.
I also checked the injectors with pressure tester (air), although I was only able to test them to 2 bar. None of them were leaking.
And connected all injectors to fuel distributor and pressed down the flap slowly. All injectors started to spray simultaneously (at approxemately 1 mm. opening of the flap), at least giving some indication that they open at the same pressure, with an intensity proportional to the flap position.
I think that this conludes, that the injection system in general is working.
The question is then, whether mixture is right for the engine to start.
And that returns me to the question whether an incorrectly working EHA can affect the idle mixture so much, that it won't start, bearing in mind that I allready replaced the EHA (who knows, maybe with a defective one)?
Does anyone know?
Or shold I try adjusting the idle mixture (with reference to other "duty cycle" postings), again bearing in mind, that it previously started fine with the current setting?
/Jens
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