323i fuel supply issue.

[David Mc]

Okay, this one is really getting to me, my Euro-spec 1982 323i was running sweetly then mysteriously cut out and refused to re-start. Thinking that the problem sounded like it was related to the fuel supply, I have done the following:-
1. Replaced the fuel pump (Brand new Bosch 0580254909) and fuel filter (Mahle).
2. Cleaned and treated every electrical terminal in the fuse box with Silicone spray, replaced every fuse in the car and cleaned and refitted all relays.
3. Refurbished the WUR (I am not a newbie at this type of thing) and air slide ( Car has run without fault for several months after this was done.)
4. Checked distributor cap (new) rotor (new) and plugs - engine has heaps of spark.
5. Checked all hoses for a vacuum leak - all appear in good condition (most have been replaced) and connections are firm.
Current situation is that if I can get the engine to run, it runs rough, then occasionally will smooth out and rev freely - but will not go over about 3000 rpm - then stops as if the ignition has been cut. If it does restart, often it will run rough and not much more than an idle speed.

To me I would swear this car is starving for fuel - I have undone the pickup from the fuel tank (under the rear seat) but the unit will only lift up about 25mm and I can't seem to manouvre it out of the tank completely, (is there a trick to this that I am missing?)
I am just about out of ideas and am now considering pulling the fuel distributor (which seems to be getting plenty of fuel, but not sending much to the injectors). Even though the car is getting on, in light of the amount of filtration in the fuel supply, I wpuld be surprised if the fuel distributor is the problem as it seems to be a fairly simple and robust unit.

What am I missing???

[quinn_656]

did you test the injectors?

[Mcinek]

I would do the injectors test.

[David Mc]

Thanks, they were next on my hit-list but I have been discounting them to some extent as the result of the random run rough/smoothe out and rev freely, then unanimously completely fail scenarios.

[Jeroen]

When and how did the problem start, after having work done? The fuel pick up in the tank needs some fiddling but it should come out fine.

But, if you have an AUS spec car the car also has an in tank pump similar to that of the E30. In that case you have a 2-part pick up. First undo the 4 inner 8mm nuts and remove the level sender, after that the pump should be able to come out. Seems likely to me this is the case and that the in tank pump is at fault.

Other option: fuel distributor arm stuck. Remove the intake air filter and go inside the air filter housing with your hand. In that way you should be able to carefully push the arm that is located at the bottom of the fuel dizzy upwards and let it come down again. Repeat that a few times and it might move again.

BTW did u check the spark plugs: are they all dry? I can't believe they would all fail at once.

[Wondermike]

can it me a mass problem or even the ignition module?

[Jeroen]

The ignition module is always a suspect but as he describes he does have a strong spark. The plugs would tell us more, if they're all wet then an ignition issue is a possibility but I expect dry plugs meaning not enough or no fuel.

[David Mc]

Great info, thanks. The problem started out of the blue, but the car does seem to have an in-tank pump as Jeroen mentions. I recall being surprised that the suction line that the Bosch pump uses was not full of fuel when I removed the intake line. Spark plugs are dry, so I think you may have nailed the problem.

[David Mc]

Okay, substituted the in-tank pump - no difference. The car is very hard to start but you can hear it fire once or twice then nothing. I was able to fire it up and run it up to about 2500rpm - it smoothed out for a while with just an occasional miss but if I try to raise the rpm, it just dies like the ignition has been killed. Idles very rough and plugs are dry. I tried lifting the fuel distributor control pin and spraying around the underside of the fuel distributor with throttle body cleaner - no difference. It has to be something simple, as I said initially, this just struck completely out of the blue, one minute the car was running as smoothe as silk and revving freely, then the engine just died and all this rubbish began.

[nige21]

If there is a wrecker near you pick up an ignition module and and dizzy, there is a reluctor sensor if i remember correctly inside the dizzy that is replacable. Pretty easy though to just swap dizzy's over.
I had very similar symptoms to you and after replacing both pumps i found it was actually the distributor (ignition not fuel).

If it turns out you have a bad fuel dizzy tho, shoot me an email, as i have one that was working great before i removed the engine.

[mbuus]

Mate I had the exact same problem with my car. Just cut out for no reason, checked all the obvious and still no luck.

Replaced the ignition module and it ran without any hitches till i sold her.