My 300E won't start. I have fuel pressure because if I loosen the fuel line to the cold start valve i get a shot of fuel spray from it. So the fuel pump is outputting. However if I disconnect one of the fuel lines to an injector and crank the engine, no gas is ejected from the fuel distributor. What we be the problem with that? Thanks for your help.
JB
88 300E 99 E55Did you have any problem starting the car before it quit on you? What are the circumstances that it quit on you?
Just to help you in how the fuel distributor and injectors work..
The injector valves will open at certain pressure difference, and the flow will depend on the pressure difference. On one side is the vacuum from the particular cylinder, and on the other side is the fuel pressure from the fuel distributor.
The fuel pressure is equal to all the cylindres (injectors), but only the cylinder, which is in the intake stroke (intake valve open), will provide enough vacuum for the injector valve to open.
The pressure from the the fuel distributor is controlled by the air mass sensor plate, which will move a plunger inside the fuel distributor to control the fuel pressure to be proportional to the air flow. No air flow will result in no fuel pressure (flow) to the injectors.
The cold start valve will simply add some extra fuel to the intake manifold for a richer mixture during cold start.
In parallel to the fuel pressure control plunger of the fuel distributor is the EHA (Electro Hydraulic Actuator), which will fine adjust fuel pressure and thereby the mixture according to control signals from the ECU.
If this is defective, it may provide way wrong mixture and thereby preventing starting. I had this problem with two different EHA's. Once replaced with a good one, it started right away.
I could of course also be other things, but I hope the explanation will assist you in the troubleshooting.
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