Motorraum: '90 750iL Elektrofrage- soll Samstag schrauben

[virtual]

Du kannst den Widerstand messen, das sagt aber nicht genug aus..........man sollte den Motor drehen können um sicher zu sein.

Aber das Teil mit 2 Leitungen in einen Eimer zu halten und eine kleine Fontäne zu werfen ist einfach und aussagekräftig.
(testweise den Finger auf den Auslaß halten, um Förderdruck zu testen.)

[Erich]

Well I thought it was the fuel pump and it still maybe. I was pressed for time so I went ahead and installed it without checking if there was fuel between the pump and the fuel filters. I checked at the engine and I still do not have any fuel to the left bank (7-12 cyls?).

Jim and others mentioned "Limp Mode" is there a way that the engine can go into limp mode and not display an EML or other warning? As I stated in a previous post I have swapped MAF, DME, DME Relays, Fuel pump relays, inductve spark check on both sides. The problem remains on the left side.

The only other thing I can think about is that I will rout a piece of hose from the sending unit to a bucket to see if I have fuel there, if so, I'll check the fuel filters. I doubt that if it is a fuel filter issue that it would have cloged so abruptly (working in the morning and not in the afternoon). Any ideas on this. If there is fuel at the sending unit the only thing between there and the engine bay is the fuel filters right?

Shogun has asked about the EML. Prior to start up it lights for a couple seconds and then shuts off.

Does anyone know of any other reason why fuel is not making its way to the engine?

Still plugging away at this, hopefully it will be solved soon.
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I tested the fuel pump in the engine bay as described in the previous post. At that time I checked the fuses again and noticed that since I installed the new pump my fuse #24 (fuel pump) was blown. I changed it out with a new one had then had my wife check the car after starting it. That same fuse is burnt out again. Is it possible knowing what I know now that the fuel filter may be pugged solid not allowing any gas to go through, in turn causing the pump to over work and blow the fuse?

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Nachricht von real Ende.

Ich suche hier in Japan mal schnell nach einem Filter.
Aber kann das sein, dass das Filter total zu sitzen kann und die Sicherung 24 fliegt?
Was ist noch an Ratschlaegen zu sagen?

[virtual]

Ja, ist möglich.........dazu müsster er aber eine Ratte getankt haben

Die Pumpen müssen um Druck aufzubauen zwangsgeführt sein d.h. der Sprit geht entweder durch die Pumpe oder gar nirgens hin.

Wenn jetzt etwas die Leitung total verstopft, blockiert die Pumpe, weil der Antrieb (Elektromotor) nich ausreichend Kraft aufbringt um weiterzudrehen.

Dabei steigt der Strom erheblich, was die Sicherung schmeisst.

[Erich]

Help! Can't find short

I checked and it appears the Cats are on correctly.

Here is what I know at the moment I attached this to the original thread before seeing this reference post:

After extensive checking I am having trouble locating the short or electrical problem that I am having.

At the present I am still blowing fuse #23 (fuel pump) but only when I start the car. If I have the key in position 2 the fuse doesn't blow. I believe is the problem may be with an overvoltage protection relay, more on this later. Here is part of what I know let me know if this gives any clues:

1. Key in off and I attempt to jumper 30 and 87 at the fuel pump
relay nothing at either relay;
2. Check with a multimeter 30 and 87 and there is nothing;
3. Turn the key to position two and I get just above 12 volts on
both relays at 30 and 87;
4. With the key still in position 2, 30 and 87 jumpered, I checked
voltage at the connector and I get about 3.4 V at 4,5 and 4,6 on
the connector;

The only time the fuse blows is when I start the car. I am not exactly sure of the direction of electricity flow but it appears to be ign coil - fuel pump relay - fuel pump - fuse, with the main (DME?)relay, DME, and some overvoltage protection relay(any one know where and what this is?) connected also.

I have just about given up here and may have to breakdown and go to the dealer to check this out....HELP PLEASE!!!

[Stefan2912]

Meines wissen nach fängt ja Die Pumpe erst mit der Motordrehzahl richtig das Fördern an.
Hat er einfach mal die Pumpe mit ner batterie laufen lassen, zum Test?
Würde ich mal machen, kurzzeitig macht das keinen Schaden an der Pumpe.

Oder hab ich wieder nur den Text falsch verstanden

Grüsse
Stefan

[virtual]

Ist normal so, ich wollte auch mal den Pumpentest machen..............
die Relais sind vollgestopft mit Elektronik welche auch noch von den DMEs ein "Ready to go" bekommen.
ein direktes Überbrücken, wo es laut Schaltplan gehen sollte, bringt bei mir nur ein "klick"............aber mit laufendem Motor (noch mehr Relais und andere Gizzmos) läuft die Pumpe einwandfrei.

Wird wohl am einfachsten sein, die Pumpe im Kofferraum zu testen.

[Erich]

Vorschrift, damit der gluehende Kat keine Braende hervorruft. Sollte also nicht in einem deutschen drin sein:

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Aber fuer USA Autos gab es mal wieder eine Ausnahme wegen des Drucks der Regierung:

An here's the section of the agreement where they decided that imports from the US didn't have to have them anymore..


Sonst nichts neues zu berichten. Er sucht weiter. Melde mich wieder.

[Erich]

und das anscheinend gleich 2 Mal. Zunaechst die orginal eingebaute, und dann die gebraucht gekaufte.
Scheint wieder zu laufen. Dank an Alle wegen der regen Mithilfe.
Folgende email erhalten:

Erich & Mike,

The car is running!!!! It is amazing what happens when you get a working
part. Thanks for the help that you and Mike have provided.

This is what i posted on Roadfly this morning:

The problem has been solved it was a fuel pump. The new fuel pump that I
purchased was defective which caused the fuse to blow. This did not occur to
me as a possibility at first so I assumed it was a short somewhere else.

In the future I suggest the following in troubleshooting a rough running
engine with no power and hard shifting. Bear in mind this is what I found
would have helped me resolve this problem more quickly:

1. Check and see if the EML light turns on during start up - No EML suggests
Limp mode;
2. If you are not in Limp Mode check the exhaust pipes between the engine
and CATS - helps identify if both banks are running;
3. If one side is hot and the other is cold than I considered the problem to
be fuel or spark related. Check the fuel supply by following the procedure
to check if fuel is making it to the engine as detailed in Johan & Sean's
webpage at:
 http://bmwe32.student.utwente.nl/sea...Regulators.htm
4. If no fuel at the engine check the fuel pumps as detailed at:
 http://bmwe32.student.utwente.nl/sea...t/Fuelpump.htm
Note: When I tested my voltage I did not get reading that were similar to
what people suggested I should get;
5. A good way to check the pump is to apply 12V directly to them. Keep in
mind that these are immersed in the gas tank and that the petrol is what
cools them so when testing do not allow the pump to run for long periods of
time. Also, because it is a pump expect a shot of petrol to come out of the
pump, use caution in where this petrol will fly;
6. If there was fuel at the engine as described above, I would consider
spark as the next check;
7. I was able to check the spark by using an inductive timing gun and
attaching the connector to the individual plug wires at the distributor. I
loosened the tubing to the MAF to provide better access;

At this point I had no electrical problem so I will not proceed any further
along this vein. Bentley's does detail a series of tests for the coil and
other electrical components.

I understand that there maybe better or easier ways to accomplish what I
have detailed above,but if this can help one person I'll be happy. Thanks to
all who assisted on this adventure!

Real

[Erich]

Also, um das mal nach 3 Jahren zum Abschluss zu bringen.
Der Anschluss am Kat fuer die Temperatur des Kat in Japanausfuehrung hat mit der DME nichts zu tun.
Gibt lediglich Alarm wenn die Temperatur des Kat eine gewisse Temp. uebertritt. Dafuer hat der japanische E32 hinten ein zusaetzliches Relais drin.
Das sieht so aus, und da sieht man auch die Temperaturen.
Und dann noch mal ein Bild eines gluehenden Kat, was so ein Temperatursensor ja vermeiden soll. Und defekte Benzinpumpen am 750

Das besagte Auto laeuft uebrigens inzwischen in Kanada.