Technical UNO Fire loss of power - stalling --pls HELP :-(

[uno169]

So, got an uno mk2 fuel injection.
Worked a dream the other day... always worked super fine.

Now this morning it suddenly stalled on me.
Couldn`t get it back to start, but after many tries I finally got it fired just enough to park it on the side.

It felt as if it was only running on 40% of its power and kept cutting off.

So, i tried:
1) replaced bosh idling actuator
2) replaced ignition module with one i had spare
3) checked dizzy cap and rotor -- seemed OK
4) exchanged coil with a friend -- still the same
5) new plugs + leads
6) checked vacum advance - OK

I am now LOST -- what else could i check ?:bang:
It runs ok in the morning, but doesn`t rev up as it used to (even though i`m 100% the bosch idling unit is working as i can see it move + its brand new!
It gets much worse when it heats up, as if not enough power is available.

Maybe Fuel pump ? Clogged Carb ? .. battery seems ok too.

ANY suggestions appreciated guys.
Thanks

 

[jo0lz]

It gets much worse when it heats up, as if not enough power is available.

Does it sound like its starved of fuel
Could be fuel evaporation due to heat?

How old is the fuel filter?
How good is your fuel pump?

I am just guesing mind you
Because i have not had anything like this happen with our MK2 1.0 SPI
Even in really hot weather on a rally across Portugal this summer
Hmmmm

SPI intake air temp sensor duff??

 

[uno169]

Well joOlz,

I have also forgot to mention I just replaced the fuel filter too.

i have never encountered any prob before not even when hot, it drived like a dream actually ! and thats why i want to fix the problem as it`s been quite reliable.

I have checked the air temp sensor which is connected on the intake manifold(the one with the blue connector right?) basically connected it and disconnected it when cold, and yes it did make a difference and stalled the engine immediately as idling unit moved back.

Could it be the pump ? where is it located and any way i can check if its providing enough fuel without tearing it apart ? anY DIY on the pump ?

Thanks for your help
Cheers

 

[Chas Uno]

Check the ignition amplifier module on the distributor (the silver finned unit). These are notorious for failing when the engine gets hot and can cause similar symptoms to those that you describe.

 

[uno169]

All ready replaced ignition amp with one I had spare... no luck :-/

I`m starting to suspect it could be the fuel pump, where is it located and any idea how it can be checked without being opened ?

 

[Chas Uno]

All ready replaced ignition amp with one I had spare... no luck :-/

I`m starting to suspect it could be the fuel pump, where is it located and any idea how it can be checked without being opened ?

Ah yes, you did say that you'd already replaced the module

However, you swapped it with a used unit didn't you? It's possible that that's also faulty though you'd be unlucky if that were the case.

Are you absolutely sure the vacuum diaphragm is ok? Did you test it for vacuum? And is the vacuum pipe from the diaphragm to the carburettor ok?

As for the fuel pump, it is an "in tank" type. You can access it via the access hole under the rear seat. Tip the rear seat forward, pull the carpet up on the driver's side and you will see an oval plastic cover. Pull/ prise this off and underneath you'll see where the fuel pipes/ sender unit and fuel pump are fitted, as well as the wires and connectors for the fuel pump and fuel gauge. You need to unbolt the nuts on the oval plate to pull the fuel pump and sender out, or you could simply listen to see if the fuel pump is operating correctly.

I would add though that fuel pumps tend to either work or they don't. Have you checked the fuel filter unit as if that's blocked that will restrict petrol flow?

BTW, you won't have a blocked carburettor as your car is injected. The SPi unit looks like a carburettor but it doesn't have the myriad of jets that can get blocked in a normal carb.

 

[jo0lz]

Well joOlz,

I have also forgot to mention I just replaced the fuel filter too

Hmm
This is another guess mind you
Cold the fuel filter be unidirectional [with a one way valve] and you have it the wrong way round???

Also I'd be tempted to get that fuel pump out of the tank anyway
If only to check that the gauze filter [sock] that goes over its intake is not dirty or clogged in anyway
This also gives an opportunity to check the inside of your fuel tank for debris/rust/grime

Oh by the way when I mentioned the air temp sensor in my earlier post I meant the little gizmo that is next to the injector in the SPI
NOT the engine water temp sensor on the intake manifold that you have diligently already checked by pulling that blue connector plug

 

[uno169]

Damn,, i`m beining to suspect that the ignition module (incl the one i had lying around) could both be faulty. Anyway i can check them out with a multimeter ?

I`m 101% sure orientation of fuel filter is correct.
I am confused with regards to the Air Temp Sensor... whch is it exactly ?

Thanks guys

Cheers