328 runs for 2 seconds

The wiring diagram is above.

 

The diagram is quite blurry, to say the least... I've had a look at the 308 diagram. There is basically one relay that's operated by the thermo time switch. This relay acts like a toggle switch (see Bosch ref 0 332 204 101, https://www.ferrarichat.com/forum/threads/a-c-woes.626912/#post-147446406). When the TT switch is activated this relay feeds (through its 87a pin) both the cold start injector AND the Pump relay (this relay is a "one way" relay type 0 332 014 113). When the TTswitch times out, it de-energized the 0 332 204 101 relay which activates its pin 87. This pin feeds the fuel pump relay WITHOUT cold start injector.

(Here again that's based on the 308 diagram, but the concept is the same for all k-jets : when engine is hot the thermo Time switch does not energize the relay, so only the pumps are activated, not the cold start injector. When engine is cold, depending on ambient temperature the activation can last up to a few seconds).

Back to the subject, I really doubt this is related to an electrical problem, as he would not start in the first place without pumps. It is possible that the car just start on the cold start injector alone, and that subsequently the main injectors do not provide the required amount of fuel (This cold start injector has its own independent feed lines that could work regardless of the WUR or distributor).

From then on, one could speculate that either the WUR is clogged or the frequency valve is faulty, which would raise pressure to the point of fuel startvation (more control pressure means less fuel).

This is all speculation, as the OP did not test pressures.

In any case cleaning the WUR is not a bad idea. And as the pump was destroyed, checking the in-tank mesh-screen filter would make sense. If this pre-filter is damaged, the pump may have swallowed whatever was in the tank and turned it into a very thin rusty power that would easily pass through old filters and make an absolute mess in the WUR and frequency valves. Was the mesh screen replaced during the pump swap?

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You did quote the pump pressure that is not very usefull. You need:

0) pump flow before the distributor under no load (0.5l~1l every 30 seconds),
1) system pressure (after the pressure regulator that's inside the distributor)
2) control pressure as modulated by the WUR (combinee with the frequency valve if you have one)

It's the difference between system pressure and control pressure that allows to balance the distributor plunger/disc against the airflow. If your control pressure is too high due to a blocked wur or frequency valve it will raise the control pressure to the point the airflow cannot lift the distributor disc, i.e no fuel.

So let me repeat this again, what is your control pressure? Without this figure we can only speculate.

If you need instruction on how to perform this test, just ask. It's quite easy with the $80 gauges being sold on ebay.de .

 

As the engine does not run form more than two seconds,it could not reach hot temperature on its own, so I assume you had to bypass the safety switch in order to run the WUR and the pumps for a handful of minutes. If so, no electrical gremlins on the k-jet side, and no pressure issues either.

Just try to disconnect the cold start injector (disconnect the Bosch junior plug), and see if the car can start. If it does not start at all this would probably mean than the fuel sent by the distributor is way to lean. On the contrary, if the car starts and run somehow better, this could be due to a leaky cold start injector that floods the engine.

 

"Well all the numbers where before the problem started"

Great, what are the numbers now that the problem started? That is what you need to know.

 

It's easy: disconnect the.safety plug from the distributor, this will force the pump to run. While you are there disconnect the WUR electric connector.

While the pump run you can check the cold control pressure and the system pressure.

Once you have the cold pressure, you can connect the WUR electric connector. The WUR has its own heating element, so after 5 minutes you will have the "hot control pressure".

In case your injector are leaky, and fill the piston with gazoline, you should remove the spark plugs and let the piston chamber dry after your testing procedure.

 

I've been following this thread closely. If I was you I would take a step back to basics pull one of the injectors stick a clear cut off plastic water bottle bottom under it and start the car and see if fuel is spraying for those two seconds that it does run....something is definitely out of whack. Go back to basics. And also check that fuel accumulator? And check that fuel frequency damper AKA fuel pressure regulator?

 

( wink)
I have a spare, one of these.

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And a 328 for a decade and I've had a 348 for a decade and neither one has ever been to a shop ever. Always figured stuff out Thanks and large part to this chat room. I subscribe to the Occam's Razor theory of Automotive Mechanics which states that "the simplest solution is usually the correct solution". Have you tried having someone spray some starting fluid in the throttle body to see if it will run for more than 2 seconds then you could at least maybe determine if you're getting spark or if it's a fuel issue?

 

That is the kind of thinking that I subscribe to. Since the problem started with changing the fuel pump,I would have first checked the wiring associated with changing the pump. Plastic harness connectors and wiring insulation become brittle with age,and also a crimp-on metal connector can become loose on the wire.

 

Per an earlier post, have you (OP) tried disconnecting the safety plug on the fuel distributer to see if the fuel pump runs with the ignition turned on (not trying to start the car, just ignition switch on)? If you did and I missed that in previous posts, I apologize...

 

Just to reiterate (because I did some troubleshooting on my 348 earlier this summe) by giving it just a puff of starting fluid as it's dying you will immediately know if it's fuel or ignition related without question

 

Keep us posted.

 

Just for the record, here is the 2019 Press Release about Bosch Classic offering. It is in French, but they indeed confirm that most hard to find k-jets parts are now available through Bosch-Classic. At the end of the PR, there is a detailed list of French Based specialists affiliated with Bosch-Classic (and presumably capable to order the remanufactured parts).

Sadly the links to the diagrams are now dead, but if you make a search with the type of vehicle they indeed list all the parts they can provide (including re-manufactured airflow sensors and WUR) : https://www.bosch-classic.com/de/en/products/vehicle-and-product-search/-/Auto_parts_and_accessories_for_vehicle_Ferrari_400_Automatic_i_1979_-_1985_232kW_F_101../vi/vehicle/SR4KIA/