I have finally given up trying to get my uno working. I no longer have the patients or money. :bang:
Should I sell the car?? Or is there people out there interested in the parts??
I am putting this thread on to see what you think??

The car is a Fiat Uno Mambo 1.0 ie, 1994, 80K miles has been looked after well by previous owners. About a year ago the car waas owned by my neighbour and he didn't have the money to do it. So I bought it off him put on a new clutch £60, and took it for a MOT. It failed on several points including the emissions. Not having the time and in need of a car quickly I went and purchased a run around whilst I fixed the uno.

I fixed all the points for the MOT including new bottom ball joint and suspension arm, new brake balance valve, new headlight new windscreen and new back box. I also replaced the manifold temp sensor as Fiat said this is what was causing the high emissions.

Off I went on another trip to the MOT garage and it passed apart from the emissions. So took it home and made some phone calls Fiat and a few other garages wanted about £100 pounds to look at it. So instead I tried a few other things and eventually found it was the lambda sensor, off to the shop and £40 later I have a new sensor. Fitted it and the car ran like a dream.
Back to the MOT garage, but this time I didn't get there.
(See attached https://www.fiatforum.com/showthread.php?t=18875)

The car went to a man who did manage to get it running for me, (£60) he said that the fuelpump wasn't earthing via the ECU so he bypassed it. Excellent I thought and off I tried to get it MOT'd, but it stopped again.
Phoned the man up he said I will have to get a new ECU, off I go to the breakers yard and get a tested ECU for £30. Put it in car and it starts straight away, runs sweet again.

Brilliant and so with a big smile on my face I jump in the car drive it 50 metres and it dies again. (not smiling anymore). :bang:
Phone man up, he no longer knows what the problem is with it and he will have to look at it again. But it sounds like an electrical fault.
So for the last few days I have been getting wet in the rain trying to find out what the fault it but I can't.

It seems like the fuel pump relays are not working properly, there is no noise from the fuel pump, and no fuel being injected into the throttle body. :bang: :bang:

Anyway unless someone can help me the car will either be for sale, or will be broken for parts. Is there anyone interested in the car or parts from it?

Dear Fishbones,

As I mentioned in my previous thread, I had a similar problem (i.e. electrical). The garage technician found a problem in 'wiring harness'. It's quite difficult to find the bad wiring, he had to open the 'Dashboard', detached the wiring harness and checked each wiring. But It works and makes me happy. I suggest you to check the wiring. Hopefully help.

Uno Lover

Hendro. N

What sounds fishy is the fuel pump 'not earthing via the ECU' diagnosis. I begin to wonder if the ECU itself is being earthed. You will basically have to start at the ECU plug (clean it with contact cleaner) and try to trace the wiring until you find an earth point.

It seems a bit silly to give up over what is probably just a loose electrical connection, after you have spent so much money replacing 'wearable' components like the Lambda sensor and exhaust back box. How much can it possibly cost to fix a loose connection or fusebox fault? Just a thought.

Let's hope that someone here can be a bit more specific on exactly which wires to check (I only know carburettor Unos, sorry).

-Alex

Have you tried...

Hi again

Electrics can do the strangest things.

With the Ignition off!! Check the earth path to the ECU as alexGS says. Use an Ohm meter across its earth point and another part of the (bare) bodywork. – see “Dia.JPG and Key~.JPG” from FIAT Porter Manual.

When your sure you have a good earth path there, look at the middle part of “Breather.jpg” re cutting out and breather hose valve. This area may be the cause as a bad tank vent/valve will not let air in to replace the “void” left when fuel is pumped out of the tank, so the fuel becomes harder to pump out and eventually the engine will not run or start (temporarily). Have you tried removing the fuel filler cap and listening for excessive hissing / sucking noise signalling not enough air flow? Also refer to "partF....JPG "– sorry if you have been there –

usual caution regarding pressurised fuel system!! – My 999 IE 1993 UNO “Start” never hisses when I take off the fuel cap. I don’t know if it should.

It may be worth checking for (out of sight) broken wires between the ECU and fuel pump see Dia.JPG and Key~.JPG for colour code and path. I think it would be a good idea to disconnect the battery first, but I don’t know if there are any dangerous capacitive parts (which store energy and could give a strong kick) or any parts which could be damaged if shorted accidentally. The problem with checking wires is that it will probably be the one you least suspect, don’t check or check last.

Hope this helps and Good Luck!!! – Louie Bee.

PS

Porter Manual ISBN 1-899238-23-9

FIAT part number 46000980

Covers ALL UNO 1983 - 1996

Out of print over the last few years – I got my copy off a guy who found them in a bin at work (F**T garage) and is selling them on Ebay.

OOOPS

I did’nt think it would look like that

Er, am I in trouble

Hello! What did you decided to do? I sent you an email but I can't read a replay! Let me know if you' re going to sell parts!
Thanks a lot,
Andrea.

Eurika ( I think)

A big many thanks to you all that have given me ideas and insperation.
Sorry for the dealy in getting back, but have been working.

Managed to get it running again. What I did was, check all the wiring as per AlexGS said. I pulled out the dash and took out the whole wiring loom for the ignition and fuel injecton system, and I found the fault.

It was a bad earth. The ECU earth was frayed and the cable that went to the back of the engine was very loose. I fixed and moved the earth to the suspension strut and all appeared fine. I also had to put the original ECU back in, because the other one was fried. All that is left to do now is change a transitor that has blown in this ECU, and all will be fixed.

Anyway a big thank you for the ideas. Hopefully it will get through a MOT.

Re: Eurika ( I think)

Well that's a relief! Well done for putting in the hard work to find the bad earth. I have a nice warm feeling inside, hoping that you get a good number of miles without any further problems - good luck!

By the way, yesterday I was driving another person's Honda Accord when it ground to a halt, the generator no-charge light being on and the battery having gone flat. The problem was not a bad earth, but a failed alternator voltage regulator. Good thing I knew someone with a spare - but there you go, bloody dodgy Japanese electrics!

-Alex