Technical Fuel injection unos

[CLXCraig]

A. do they exist? if not this thread is preety pointless.

B. If they do, does anyone who owns one ever have problems with loss of power up hills? I get this problem in my panda so you guys might be able to help. i think it's to do with the way the fuel is sprayed into the manifold.. It seems to me that when going up hill, gravity takes effect and it gets sprayed onto the side walls and then dribbles in instead of being sprayed. thus fuel not getting to the cylinders in time..

If none of you guys experience this problem, then perhaps a uno injector would work better for me.. or would it be to do with the managment and how much fuel the ECU tells the pump to pump?

All answers appreciated!
Craig.

 

[Chas Uno]

A. do they exist?

Yes. The "i.e." you see on a lot of Uno models stands for "injection electronic" (in Italian though). All UK cars registered after January 1993 have to have fuel injection because of the legal requirement to fit cat converters (carburetors aren't accurate enough and will damage cats over time). All later model mk2 Unos are therefore fuel injected, with the 999cc models sharing the same engine and injection systems as the equivilent SPi Pandas.

B. If they do, does anyone who owns one ever have problems with loss of power up hills? I get this problem in my panda so you guys might be able to help. i think it's to do with the way the fuel is sprayed into the manifold.. It seems to me that when going up hill, gravity takes effect and it gets sprayed onto the side walls and then dribbles in instead of being sprayed. thus fuel not getting to the cylinders in time..

First things first. Are you losing power only when going up hills, or are you only noticing a loss of power when you go up hills? This needs to be determined before investigating further.

Secondly, interesting theory you put but despite what the people selling injector cleaners would have you believe, injectors tend to dribble fuel in pulses rather than spray. Also, gravity would have little effect on the fuel entering the inlet manifold as it's the manifold depression (vacuum) that sucks the fuel in and (if my knowledge is correct) causes it to mix/ vapourise with the air also being drawn in. The volume of gas flow through the inlet manifold is immense (we're talking cubic feet of air per SECOND!), much more so than a vacuum cleaner, which I'm sure you are aware can suck things off the ground in the reverse direction of gravity. Thus we can rule out gravity and fuel dribbling down inlet manifold walls being a problem

What could be the problem is fuel starvation caused by a low level in the fuel tank that means the fuel pump pickup pipe is being starved of fuel when going up hill. Or you may have a weak fuel pump (or fuel pressure regulator?) that only manifests itself under wide throttle openings, again such as when going up hill.

So before going further, try and identify any other information that may point to a diagnosis. Is fuel consumption normal? Is performance normal under all other driving? Are there any changes that you may have noted in engine behaviour recently? Is the engine tuned up correctly/ serviced recently?

Oh, and a 999cc Uno SPi injector will most likely be the same as that in a 999cc Panda so there would be no benefit to fitting one. Unless of course your Panda injector is faulty.

By the way, how come you're asking in the Uno section rather than the Panda section??!!!

 

[CLXCraig]

Cheers for all that Chas.

I only notice loss of power when drving up steep hills at about 50+ then it drops and i end up in about 3rd struggling up the hill at about 25. as far as i know the injector works fine, so your probably right about it being the fuel pump, although i've experienced this with a full tank.

I knew the pandas struggled on this front so figured if i asked in here and the answer was the same then its a fiat problem, if not then its a panda problem

 

[Most Easterly Pandas]

Craig, we've only Automatic and not Manual injection Panda's, but they go up hills fine at speed, both high and low, and accelerating when going up-hill. So could well be a fueling problem?

 

[Chas Uno]

Hmmm, if it only happens up hill then I can only think it's fuel pump/ fuel tank related. One other thing worth checking is the fuel filter itself, as if it has become blocked then it will restrict fuel flow.

Are you experiencing 'pinking' (a metallic tinkling sound) at all when going up hill? Also, check your spark plugs and see if they're the correct colour - they should be a light biscuit colour. If your Panda is running weak (reduced fuel flow) then it it could manifest itself as the above symptoms.

 

[CLXCraig]

Plugs are fine they got cleaned and re gapped just after christmas. worth checking the filter.. it does look like the original! Fuel pump is worth checking too, i do remember rocking the car once and hereng something rattling in the tank.. so maybe something has broken off...

 

[Most Easterly Pandas]

Plugs are fine they got cleaned and re gapped just after christmas. worth checking the filter.. it does look like the original! Fuel pump is worth checking too, i do remember rocking the car once and hereng something rattling in the tank.. so maybe something has broken off...

Rattling in tank, or sloshing of fuel? Might be worth removing pump/sender and checking it's in tack. Not to hard, just put rear seat forard and up, roll boot matting forward and lift round plastic disk thingy. Then unscrew the retainer on top of tank

 

[Chas Uno]

Plugs are fine they got cleaned and re gapped just after christmas.

If the problem has only just manifested itself it's worth taking one out to have a look as the colour of the electrodes can be a very good indicator of possible problems.

How old are the plugs and how many miles have they done?

 

[CLXCraig]

Plugs have been on the car since iv'e owned it, over a year but not sure when they were fitted. I'll give taking the sender unit out a go tomorrow if it's light when i get home from work. bit worried that if anything does break off it'll be sat in the bottom of the tank..

 

[Louie Bee]

Oi get back in your own section :devil:

... bit worried that if anything does break off it'll be sat in the bottom of the tank..

It won't matter, as the electric pump can't suck it up. In less it's the gauze which has fallen off

I'd say don't bother checking inside the tank till you've ruled out the fuel filter.

If the fuel pump had a problem, you'd hear it cutting out / making extra noise if something was in there that shouldn’t be, or if it wasn't submerged in fuel, it speeds up, and you'd hear a whizzing sound.

Could be wrong here but I don't think the fuel pumps have an in between state, they either work, or don’t and if it stopped working, the car would stall within seconds