As the title mentions: my 1988 190E starts for 2-3 seconds then stalls.

As I understand it, this is because the cold start injector gives it enough fuel to start for a couple of seconds. It is obviously not the ignition, or the fuel pump or fuel pump relay because I have checked all, and it does run for 2 seconds or so.

so I have narrowed the problem down to where the fuel delivery is failing. It is going into the fuel distributor but is not getting to the individual fuel lines. Thinking it was either the fuel distributor or the EHA valve, I replaced both.

I am on my 3rd fuel distributor now and it is still doing the same thing.

If somebody has a diagnosis for this please help. I have been struggling with it for 2 months now.

Other observations to narrow it down:

-No fuel pressure on the fuel return line.
-No fuel flow/pressure through the fuel distributor to the injector lines.
-Adequate fuel pressure into the fuel distributor.
-Adequate pressure to the fuel pressure regulator.
-Adequate pressure to the cold start valve.
-Fuel pressure regulator opens at about 90 psi with compressed air.
-Replaced: fuel pump, fuel filter, fuel distributor, fuel injectors, EHA valves, ignition coil, rotor, cap, wires, spark plugs, and valve stem seals!
-Car had not been run for 4 years.

I have searched all over the internet for answers to this question, but have yet to find a solution.

Thanks!

While it is running for 2-3 seconds, does the airflow meter vane respond? If not, it may be gummy or you may have an air leak (alternate air path from a ruptured air hose).

Another thought - you say line input pressure at the FPR is adequate, and the return line opens at about 90 psi, but there is no flow in that line. This is a contradiction. Input pressure must be below 90 psi, or there would be flow back to the tank. Have you checked the accumulator too?

Steve

__________________
'91 MB 190E 2.3
'08 RAV4 Ltd 3.5
'83 Lazy Daze m'home 5.7

Airflow meter does not respond to variation. There is never fuel pressure at the injector ports on the top of the fuel distributor. Once I had a small amount of fuel pressure on 1 cylinder when I cracked the lines, but every other time no pressure.


I have tried bridging the 15 and 87 pin on the fuel pump relay to have it always on, and when it is on it will continue to build up pressure but not return any fuel through the return line. The fuel pump eventually draws enough current to drain the battery so it will not start. I have not verified the input fuel pressure, but it continues to build up to the point of increasing the load on the fuel pump- perhaps there is something wrong with this, but I am not sure what it is.


I will check the accumulator next, but I don't understand how this could be the problem if I have fuel pressure. The accumulator is mostly for warm starts, and to dampen the fuel flow fluctuation.

By the way, thank you for the response!

If the airflow meter vane does not move with the engine running, you will have little or no output from the fuel distributor. There is a direct linkage from the vane to the fuel distributor plunger, which regulates output flow to the injectors. The airflow path must pass the vane. If the vane moves easily when pushed, but not with the engine running, you have an air leak in the intake.

I also think you are telling me you haven't actually measured the fuel pressure. The pump must be capable of around 100 psi. If you are inferring adequate pump pressure just because you have flow, this method will hide a weak pump.

Steve

__________________
'91 MB 190E 2.3
'08 RAV4 Ltd 3.5
'83 Lazy Daze m'home 5.7

Do a Direct pressure test from the delivery line, without a "T" fitting. Post your direct pressure reading. With the T fitting between the delivery line and FD, you need 80PSI. Did you check your tank pick up screen? Get a new O-ring first, and remove the cylindrical strainer from the center of your tank. Its probably all "greened" up... Sediment, fuel component breakdown and varnishes, will clog that screen just sitting unused for 1 year, not even imagining what 3 or 4 years could bring.... Clean it or replace it. If its really gooey when it comes out, you must do a tank removal and get the tank flushed, boiled, or steamed cleaned. If you dont service the tank properly, you will have fuel problems again. Check the two large hoses from the idle control solenoid, Ive heard they do pop off if you have a back fire, or they just slip off sometimes. Dont forget the accumulator, plug the smaller return line from it to see if you can pressure up again.... Dont ever pinch the lines, they will crack and add more debris into the fuel system. If this doesnt help, get a multimeter hooked up to one of the pumps, you need a solid 13.5 volts there while running, perhaps 10.8 to 11.8 while cranking. Hows the battery? Try a hot newer one..... When checking for injection at a cracked injector line, you must lightly depress the fuel plate, approximately 1/4 inch or more, thus moving the metering plunger down enough to activate fuel dispersal. Did you use a used coil? Check your spark color, it must be whitish blue, with an audable snap. If its redish orange, your coil isnt making enough HT.

I didn't see it mentioned so I will suggest that you check your fuel/air mixture settings. It sounds like a lean condition. The fuel/air mixture screw is between the fuel distributor and throttle plate.