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[Horizontally Opposed]

Hey guys!

My pump has been noisy for almost two years now but I never had the money to replace it.

The past few months have been worse though since the noise has increased and I can't stand to hear my alfa like this any more.

Also, the car has been very shaky at low rpm when I take my foot off the gas .
We ran a diagnostic at a friends garage and there seemed to be no problems registered in the ecu so I took it to an original bosch service store.
Another ECU diagnostic was performed and no problems arised.
Then we checked the spark plugs and their cables, the distributor, the lambda sensor (which turned to be ok after 160.000km - weird) and finally we got to the fuel system.

The readings on the fuel pressure gauge were erratic from the moment we switched the ignition on, to engine running on low rpm, to engine running at 86C and 4000 rpm

I haven't noticed any signs of moisture on the tank but I definately have to remove it from the car and check it out.
I hope it 's not too bad

I'll definately get a new fuel filter but I'd like to at least get away with fixing the pump instead of buying a new one.

I've always thought that the pump couldn't be opened and that's what the mechanic also told me but I'm glad to hear it's been done!

Gritsop could you please share any advice/photos on how to open the pump?

I was also thinking, since the tank will be removed, if there's any way to actually make the fuel sensor give sensible readings! Anything to try from inside the tank?

If not, I was thinking of doing it electronically somehow. Use average readings every 2 seconds or so....

[gritsop]

Hi,

The noisy fuel pump is caused by the presence of foreign material inside the tank; rust of course that blocks fuel all the way to the engine.

About the pressure gauge you installed: do you remember the readings? I'd like to notice that if you feel your car shaking it means that fuel supply is not the one actually needed, it is lower => fuel pump works beyond its limits which means overload, higher working temperatures and eventually one day will say to you "Goodbye Vienna"!
Also the ECU has a way to correct the fuel supply of the pump marginally by increasing or decreasing it a bit. It looks that your case is the one that lies beyong the marginal amount of correction... It needs by all means to be inspected.

My advice for you is to take out the tank, open the pump and replace the fuel filter. Unfortunatelly I don't have pics...

Taking out the tank: rather easy job if you have support stands to place the car upon them. I had placed them under the rear axle bar which gave enough space to work from the under. Two metal strips hold the tank in place and various fuel hoses which I advice you to replace (if I remember their size is 8 & 12 mm but don't trust me 100%)
You can clean the tank using water in order to take out the vapors as they can cause serious problems if they explode. A sign of rusted tank is the brown color located in the center of the tank where a small area like a container (λεκανάκι) is formed, most of the times.

Dismantiling the pump: If you look at the nozzle that sends fuel to the engine you 'll notice the aluminium casing being bent in order to hold the plastic support that has the power connection and nozzle upon it. You can bent it with a flat screwdriver in order to make the tube again a circle one. Then little by little moving the plastic part up/down/right/left you will take it out (sometime ) . Be careful not to cut the rubber O-ring between the aluminium tube and plastic support.
Then clean the inside with plenty of fuel and especially the small filter located in the intake of the pump.

About the Lamda sensor. As long as the engine runs perfect without problems in ignition which send unburnt fuel to the exchaust your L sensor will have years to live. Many owners not knowing what service and maintenance of a car mean, have their cars running poor and when problems arise, they blame everyone except themselfs

Also have you had the injectors cleaned by the supersonic method? and by the way is your Alfa Jetronic ECU equipped?

Finally, about the fuel level gauge, I don't think you can do anything about it.

Hope I helped a bit.

Edit: take a look also at the following topic which is correlated
http://www.alfa-pages.co.uk/phpbb2/viewtopic.php?t=1568

Regards,
_________________
Thanassis Gritsopoulos
1991 Alfa 33 1.4 IE
2001 Alfa 147 1.6 Distinctive

http://www.alfa-restoration.co.uk
Parts Shop: www.alfa-restoration.co.uk/shop

[BILL]

The fuel pressure ,when the engine is stoped,that the pump is giving should be around 2.6 to 2.9 bar.I had my fuel regulator replaced 3 years ago with a used one and thats the presure it should give(my repair man said it actually ).

[Horizontally Opposed]

Thanks very much for your help Gritsop!

As soon as I have some time and a way to lift the car I'll take out the tank and see what I can do!

After that is done, I'll try to dismantle the pump!
Thanks for sharing that info! Everyone insists that the pump cannot be dismantled without breaking it and I'm very glad you proved them wrong

I guess our cars are more or less the same.
Mine is the 1.4 IE (1351ccc) and has the LE 3 Jetronic injection.

My father took the car to an injection service store some time ago and he said the guy there cleaned the injectors, but I'm not sure how he did it....
I prefer to know exactly what is done on the car and how but unfortunately since it is not entirely mine it doesn't get the attention it deserves.

The fuel cap rubber boot topic is very interesting!
I'll check mine as soon as possible!

Thanks again!!

[TOAD1]

I've used a Pug 405 fuel pump in a 16v 33 racecar.. cost 20€ from a scrap yard. Most European cars use bosch pumps so they can be found easily. just make sure it's the same size or bigger (as in a 405 pump)