There was someone on Benzworld about 5 years back with the same problem, and I think it turned about to be his MAS (the air plate thing).

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Prost!

I am rereading all the posts and systematically trying these process now. I cannot believe that all my fuel injectors could be clogged, but am tending that way now. I checked the cold start injector yesterday. There is fuel pressure to it, but with the fuel pumps on and the air flow plate pushed down, there is still no sound or smell of fuel.

I am rereading these posts and will check fuel pressure to all the injectors today.

Okay , here is an update I have checked the FD upper outlets to find they are dry. I've tried jumpering the 7-8 to get the fuel pumps to run continously. When pressing down the airflow plate thete is still no sign of fuel (ether a chirp or sound or smell of fuel). There is good fuel pressure to the bottom of the FD ( by loosening the return line I get good spray and flow). Same on pressure measuring port. When I break the cap on the cold start injector there is good fuel pressure and fuel, however it is obvious that that is far as the fuel is getting. That injector is not opening either. I have tried loosening the upper FD lines (several at a time) and using either the 7-8 cross jumpered for fuel pump running and also with the fuel relay reinstalled to crank over the engine. All the upper fittings remain dry.
These are all the same indications I had before rebilding the Fuel Distributor (FD). What can I check next?
And I told my dad this would be an easy fix Help

Jeff

Have you changed the fuel filter? It is located in the fuel cluster just aft of your right rear wheel. That cluster includes two fuel pumps. BOTH must run, the filter and a valve (don't recall the name) that maintains fuel pressure for easy restarts.

The entire cluster of components is easy to dismount and test or rework on the bench. Clamp your fuel line closed before removal. Inspect your filter carefully. If it shows signs of serious contamination, you may be faced with removal and cleaning of the fuel tank. Not uncommon after extended storage.

Just reread the posts and found that you did change the filter. Check it again. If the tank is seriously contaminated. it could be clogged again.

Ive seen the injectors get stuck and not squirt fuel , get a small punch and hammer and with the fuel pump bridged or key on lightly tap the top of each injector at the cylinder head side, worth a try

Lots of fuel and the accumulator is working well also. I used a rebuild kit and made sure that I took my time on the FD. I should at least get some fuel through the cold start injector shouldn't I? I have plenty of pressure and fuel to it, i.e. I've been sprayed pretty good when I break the connection to the injector, but that is where the fuel stops. There is no audible sound of fuel reaching the manifold. No smell of fuel. Thanks for your reply every little bit helps. Makes me think

It may be time to suspect the fuel pressure regulator. A certain minimum fuel pressure is required to open the diaphragm valves in the FD, irrespective of the position of the sensor plate and metering plunger.
Cracking the fuel supply and return fittings may produce what appears to be good pressure, however, absent measurement of pressures, that is not definitive.

Just an update for all of these posts, and thank you very much.

The update:

I could not hear the fuel pumps run and after testing them, I ended up replacing both fuel pumps and the fuel filter. I replaced the fuel relay also. I drained the fuel tank and ended up replacing the fuel tank outlet hose that was rotting a breaking up as I tried to cut a piece away.
Now I had excellent fuel pressure, still no start.
I checked for and have good spark, when I used starting fluid the engine started immediately for a second or two.
Next step, I noticed that when I broke the connection between the fuel injectors and the fuel distributor that I was getting no fuel. When I cracked the EHA or fuel in line to the fuel distributor I had good pressure and copious fuel. I had read that the fuel distributor could gum up from the ethanol fuels and I ended up rebuilding the fuel distributor. The inside was pretty clean, but the diaphragm was starting to degrade. Anyway with that done I still am not getting any fuel to the intake.
I don’t know if the EHA is the correct term for the part on the fuel distributor, but it appears to be a electro hydro mechanical fuel shut off from what I have read. I applied 12 volts to the EHA and could hear a faint click like it was opening. With a small rubber hose I blew through the unit and it opened and let air through when I applied voltage, so I don’t think it is that. I have the KE-Jetronic fuel system.
I am trying to educate myself on the Bosch CIS system, and I believe with the cold start part of the system that the engine should start, at least try to start, as long as there is fuel to the system. If anyone can help me determine where the road block to the fuel is in my system, I would be greatly appreciative.
Things I have done so far:
• New Battery
• New fuel relay
• New fuel pumps
• New fuel filter
• New fuel tank exit hose
• Fuel distributor rebuild
Update: I have checked the FD upper outlets to find they are dry. I've tried jumpering the 7-8 to get the fuel pumps to run continuously, then pressing down the airflow plate there is still no sign of fuel (ether a chirp or sound or smell of fuel). There is good fuel pressure to the bottom of the FD (by loosening the return line I get good spray and flow). Same on pressure measuring port. When I break the cap on the cold start injector there is good fuel pressure and fuel, however it is obvious that that is as far as the fuel is getting. That injector is not opening either. I have tried loosening the upper FD lines (several at a time) and using either the 7-8 cross jumpered for fuel pump running and also with the fuel relay reinstalled to crank over the engine. All the upper FD fittings remain dry.
These are all the same indications I had before rebuilding the Fuel Distributor (FD). What can I check next?
And I told my dad this would be an easy fix Help
From what I have read fuel pressure is very important. If it is too high will a valve stop it from flowing into the top of the FD?

I will be posting pictures of some of the items on or around the intake manifold and CIS that I am unfamiliar with. Maybe you can help me with the identification. I feel that I know what the fuel pressure regulator looks like. Does it work after the fuel return line from the fuel distributor? I think that I have read that fuel pressure is regulated after the fuel return from the FD. I imagine that to find the correct pressure inbound to the FD that I can open a threaded plug on the bottom portion of the FD and see if I can measure the pressure there. I'll try to get that done by tormorrow. Thanks for your reply

The "cold start injector" serves more like a choke. When the engine is cold, it sprays fuel to enrich the mixture. You still need the other 8 injectors functioning to start the engine.

Cracking the fuel lines tells you nothing about pressure. You need to connect a fuel pressure gauge (google for that information) and see what kind of pressure you actually have.

__________________
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Getting fuel through the fuel distributor is all mechanical. When the center plunger is pushed up by the air meter, it lets fuel flow to the top and on to the injectors. Here you can see him pushing it up with his finger in a test rig.
https://m.youtube.com/watch?v=hRLorXbL1Us

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Regarding the youtube video referenced above (post #28), the fuel distributor used for the "demonstration" is from a K-basic system, and the diaphragm valve springs operate in a manner that is the opposite of those found in the KE fuel distributor, which is the subject of this thread.

Thanks, good video, the follow up videos are even more enlightening. Much appreciated.