I am working on 1992 190E 2.6L KE Jectronic. Engine would not start, no fuel delivery to injectors. Once I install the Jetronic test pressure gauge I get the engine to start with gauge valve open, meaning I am providing fuel pressure from system to control and I get 5.5 bar system pressure, when I close the valve to measure control pressure I get 4 bar and engine dies, goes too lean to run.

I have tested the EHA valve for resistance 19.5Ohm and current 20mA at key on. At idle I get 0.5mA.

I haven't found much information on control pressure being too low issue, other that one guy saying most likely "spill port orifice" is clogged inside the distributor.

What say you?

In the KE system control pressure = system pressure at all times.
Can you provide pictures and/or drawings of your gauge connections to the fuel distributor; it is not clear what connections you have made.

Do you even understand how KE Jetronic system works? Control pressure is different than System pressure. You are indicating that system and control is the same, this tells me you don't even understand the basics of K Jetronic fuel distributor operation.



I found what the problem is, EHA valve was stuck shut, meaning it wasn't regulating any pressure from System to Control sides of fuel distributor. In a way it wasn't providing any pressure to lower chamber. I tried using air compressor to unclog the EHA valve but that didn't work, what worked is turning the EHA adjusting screw 2 turns counterclockwise, then I felt something give inside, then I turned it back 2 turns clockwise and I was able to blow small amount of air trough EHA valve ports. There are metal plates inside that bind together and the car sat for 10 years, so I assume old fuel varnished up in there and got the plates stuck shut.
For now engine runs fine, but will buy new EHA valve when I get a chance.


I home this helps someone

On the menu this evening, prepared to your order, either whole or half:
Corvus Brachyrhynchos!!
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Herewith a useful document, of high resolution, that may be enlarged and is suitable for framing:

Attached Thumbnails

 

Checkout the fuel accumulator. This attached link is the failure analysis report, and it has a link to the easy to do test.

KE fuel accumulator destructive failure analysis

Duke