190E won't run more than 5 seconds..

After installing the rebuilt 102 engine in my 88 190e the car won't run for more than 5 seconds...Turn the key off...wait another minute...runs great for 5 seconds..

This is strange. The engine was getting fuel before the rebuild (it was rebuilt due to a burned piston of #4 cyl...whole other story)..and all I did was take the intake manifold off the head before I took the head to the machine shop. The intake manifold, complete with the fuel distributor was stored in the shop. I DID remove all the injectors and replace the seals ..and the lines were removed from the fuel distributor for that time. Is it possible that dust or dirt entered the outlets of the fuel distributor and now it won't "distribute"? I also recall removing and installing the Electro Hydraulic actuator at that time as well....

Also, when I cracked all the nuts on the top of the FD, pressed the plate down all the way and had a helper crank the engine, there was a flow (slight) of fuel out all four holes...not a pressurised stream that would shoot into the air...more like a dribble..significant?

I know I'm getting SOME fuel pressure because with the engine cold, left overnight, I pushed the sensor plate and it was quite a lot easier to move than when the system was pressureized by turning the key ON and waiting for the fuel pump to run for a second or two. Is it enough fuel pressure? Is ther a way to tell without putting a guage on it? (which, I have heard, will damage the FD by blowing some seals?)

Silly Question #1: Why does the engine start and run fine when I remove a screw in plug from the side of the FD body? This plug is an M12 head bolt about 3/4 inch loing located just below one of the injector outlets

Silly Question #2: What does the "Electro Hydraulic Actuator actually do, and can a faulty/badly installed one cause the symptoms I am experiencing?

Silly Question #3 can this whole thing be just a dirty fuel filter? The car did sit for 3 months indise a heated garage while I had the engine out.

Reply to
John Harriottt
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Clearly there's a fuel starvation problem. The fuel distributor is a complete mystery to me so I'll say nothing about it. However, the electric fuel pump is a possibility - perhaps not the pump itself but its control system. The fuel pump relay is designed to run the pump for a second or two prior to starting the engine to build fuel system pressure. That seems to be happening. But then the fuel pump should run as soon as the engine fires and it could be that that's not happening. The pump is supposed to stop whenever the ignition is ON but the engine is not running - that's to prevent a fire after a collision in which the engine is stopped.

If you can check the fuel system pressure after it stalls I believe you'll find it to be zero; that may confirm the above hypothesis.

And of course the fuel filter is still a suspect, until you replace it.

Reply to
T.G. Lambach

Hi John,I know a way to check whether there is pressure in yr fuel system ,after yr engine stall simple remove the injector fuel lines .If u get fuel rushing out u know u got pressure.Hope this help.

Reply to
camle93

I have seen people hook up the main fuel lines backwards and this has happened......

Reply to
Karl

Running for 5 seconds could quite possibly mean you are getting fuel form the cold start valve but your primary fuel supply is not working. I just went throug hthis on my 633 and wrote it up. I've never worked on a 190 but the sitation is the same for older injected cars and my guess is you have a main relay and fuel pump relay so give this a go. The theory doesn't change and to an extent all injected cars have similar design.

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Reply to
Richard Sexton

Reply to
Joe Caneen

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