Technical Throttle problems!!!! Please help

[wi11]

Hello all, i must say this is an excellent site and helped me fix the heating already in my uno!

ok, i have an L reg 1993/4 fiat uno fire 999cc engine, (10700 miles on the clock!)
Fiat certainly know how to make engines!
The trouble is that when accelerating my uno suddenly loses power ;-(
Quite dangerous considering i use it around town having to pull out quickly often!
The car will suddenly lose power and i suspect that it is due to the variable resistor that the throtte cable moves on the engine as i have checked the cable is moving lovely and freely!
At other times when the engine does decide to provide power it is excellent, smooth and suprisingly fast from a 1litre engine!
This problem only seem to happen intermittently i can't pag it down to hot/cold engine as it happens with sould destroying regularality!
What do you think it could be what would you try?

Please help!

PS. where can i get a dashboard clock from?

PPS. alexGS your a legend i have read so many post where you have hekped others and i have used your advise loads!

 

[andyjkd]

Hello all, i must say this is an excellent site and helped me fix the heating already in my uno!

ok, i have an L reg 1993/4 fiat uno fire 999cc engine, (10700 miles on the clock!)
Fiat certainly know how to make engines!
The trouble is that when accelerating my uno suddenly loses power ;-(
Quite dangerous considering i use it around town having to pull out quickly often!
The car will suddenly lose power and i suspect that it is due to the variable resistor that the throtte cable moves on the engine as i have checked the cable is moving lovely and freely!
At other times when the engine does decide to provide power it is excellent, smooth and suprisingly fast from a 1litre engine!
This problem only seem to happen intermittently i can't pag it down to hot/cold engine as it happens with sould destroying regularality!
What do you think it could be what would you try?

Please help!

PS. where can i get a dashboard clock from?

PPS. alexGS your a legend i have read so many post where you have hekped others and i have used your advise loads!

sounds like sparkplugs,leads or air filter clogged.Also could be your fuel pump clogged up.

 

[blackstart]

I had the same problem with the same engine I think - 999cc injection. The problem was with the throttle position switch. I unplugged it and it runs fine once warmed up. Prone to stalling until it does though..

Cheers,
Bri

 

[alexGS]

The trouble is that when accelerating my uno suddenly loses power ;-(
Quite dangerous considering i use it around town having to pull out quickly often!
The car will suddenly lose power and i suspect that it is due to the variable resistor that the throtte cable moves on the engine as i have checked the cable is moving lovely and freely!

As Blackstart already said and as you suspected, that throttle position sensor sounds a likely suspect to me - but unfortunately I don't really know what I'm talking about with the fuel injection Uno FIRE as I haven't had one or worked on one! On some engines (e.g. the Mk1 Uno Turbo) the 'sensor' is just a switch, and as such you can pry it apart and clean it. I think that it is also just a switch in your case, and I also think that the main function is to reduce the fuelling when the engine is idling. So, it would make sense that if the switch did not open correctly, the engine could be under-fuelled during acceleration. Maybe try unplugging the switch as Blackstart did, and see if the behaviour becomes more consistent? I would expect the idling to be slow and rough (over-fuelled), but the driving should be better?

One thing - perhaps keep the idling to a minimum during this test, because the over-fuelled idling may damage the catalytic convertor that I assume a '93-'94 Uno will have. So, perhaps warm the engine up first, then disconnect the switch and go for a drive without too much heavy traffic.

You could test the switch with a multimeter, but I think that taking it apart/cleaning it would be a good thing to try - or just replace with one from a wreckers. Also pay close attention to the 'click' of the switch as the throttle opens - is it clicking at the same point each time?

PPS. alexGS your a legend i have read so many post where you have hekped others and i have used your advise loads!

I almost cried. You're much too kind - all I do is type ideas and suggestions, the others still have to do all the dirty work, y'know. And, I have made mistakes with the Uno models I haven't seen (like yours). There are lots of other forum regulars here who will have more specific advice. I tend to go for the 'try it and see' approach, which sometimes takes longer or requires access to spare parts. I think you should always trust the person who has actually fixed the problem first. Which frequently (as in this case) won't be me. I try to make it clear in my posts whether I have actually fixed it, or whether I am just surmising...

Thanks anyway!,
-Alex