Majority of the time our FucT FiaT 1.0i.e. FIRE '93 Mk2 starts first time on the button with no problems whatsoever

VERY occasionally it will start, fast idle as normal, then without any warning slow done to normal idle speed, which when cold means it usually stalls. [usually as you try to move off]
If it has done this the only way to get it to start again is throttle to the floor and crank it till it fires up, coughs, splutters, idles slowly for a very short while, then revs pick up and you can take your foot off the gas pedal and it fast idles correctly again

The times I have checked the throttle position plunger thingy on the SPI it always seems to work OK [though not done this immediately after a stalling incidence I have to admit]

So I got to thinking [guessing] could the problem possibly be a dodgy temp sensor on the intake manifold? [or the wiring to it?]

What do you think?
Anyone else experienced the same issue?
It's only happening now we have cold weather
As it was starting perfectly fine all summer/autumn

Ta Jo0Lz

same happened to my uno.. during cold winter had to throttle in order to fire the engine. than i just left it coughing and readjust idle screw so it runs with a bit higer revs. now works great

NAH mine is different
Its fine most of the time, starts and idles sweety
BUT
Very occasionally . . .
Its as if some times the cold start [auto choke] does not work!!!

Want to fix it before it starts to happen more regularly . . .

it has now started to happen more regularly
It will start if you floor the gas pedal
BUT chugg CHuG CHuG chug for a bit
then seems to clear its self as the revs rise
but then sometimes stall as you go to pull away

Anyone have any idea what I need to try changing to cure the problem?

I'm guessing it is the cold start system as once it is running/warm its perfectly fine . . . .

Is the throttle cable too tight and / or an ECU reset due?

Try changing the the coolant temp sensor.

Louie Bee said:

Is the throttle cable too tight and / or an ECU reset due?

Click to expand...

Ta, will try those first as easy enough to do for nowt

panda1408 said:

Try changing the the coolant temp sensor.

Click to expand...

will try that second . . . .if I can get my hands on another one...TA

If I start my LGD uno from cold, it will stall everytime. I won't even start the engine - I have to rev her just to get the car started.

Low idle, ECU reset or timing need looking at I think.

Ucof said:

Low idle, ECU reset or timing need looking at I think.

Click to expand...

The idle is fine when it starts fine
Timing was spot on in Dec when I adjusted it for the MOT
Doing an ECU reset this morning

panda1408 said:

Try changing the the coolant temp sensor.

Click to expand...

jo0lz said:

will try that second . . . .if I can get my hands on another one...TA

Click to expand...

Seen one new on eBay for £25 quid
Does that seem a good price?????

Joolz- i was talking about what needed looking at on mine

the coolant temp sensor of which you speak; is it the one that screws into the block and controls the little needle thing that tells you how hot the engine is and when it is time for sandwiches?
If so, i still have the one the louie sent me which i am more than happy to post to you, after mine started working again when i hit it on the floor a few times

The coolant temp sensor screws into the intake manifold, it has a blue connector. It tells the ECU what temperature the engine is so it can adjust the mixture. You should be able to get one from a motorfactors for £10 or so.

There are two types, one with a chamfered end and one without. I am right in thinking all the injection Unos used the bosch system with electronic distributor, like Pandas from 92 to 93? If they do then you need the sensor with the non chamfered end. The sensor with the chamfered end is used on the later weber system used on later Pandas and early Puntos.

My Panda was returning low MPG so I decided to change the sensor, when I fitted the new one it caused me alot of starting problems. When I tried to start the car it would instantly die, then it would take about 5-10 seconds of cranking to get it going again, it also died a few times when you started driving and would then refuse to start again. Sounds similar to your problem Ucof.

I did various ECU resets(as described in the Haynes manual) and tried another new sensor and the original, they all did the same thing(I did actually fit the wrong type of sensor originally so that may have something to do with it) In the end I had an ex-Fiat mechanic look at it, he diagnosed a broken vacumm advance, I changed that and then disconnected the battery for 10 minutes and it now starts fine. (Although the oil light now stays on after startup for a few seconds, which I think may be related somehow)

Have a look at the threads in the Panda section titled 'Low MPG' and 'Idle Speed CLX Inj'

Ucof said:

the coolant temp sensor of which you speak; is it the one that screws into the block and controls the little needle thing that tells you how hot the engine is and when it is time for sandwiches?

Click to expand...

NaH matey its the one into the intake manifold that tells the ECU to tell the SPI to go into cold start mode

DOn't think I need it now anyway...?

CHecked the throttle cable, no way is it too tight [but thanks for the tip L Bee]
Pulled the plug on the coolant temp sensor in the intake manifold, tried starting him up...no go....plug it back in...heard the fast idle plunger move...turned over the engine..started first time...repeated same process again just to double check...got same result
So it seems the coolant temp sensor in the intake manifold is working OK
Then took the battery leads off....
Check fluid levels while the ECU did a BRaiN DuMP
Topped up washer bottle
Topped up rad, noted not loosing as much water now since I have replaced the pressure cap
Topped up the engine oil, was low because my rocker gasket has started leaking, as well as the old O ring on dizzy as well....NoTe to self...fix those LEAKS....
Battery leads back on
Turned him over
Started first time
Left him to tick over till hot while I gave him a vac out
Got up to proper operating temp
Heard the rad cooling fan come on
Cleared out a load of junk from the boot, less weight = more MPG
Heard the rad cooling fan come on a second time
SO ECU reset and I turned him off

Since them he has sounded like he is running better and has started on the button three times this afternoon.

Next test is much later this evening as i'm collecting Sarah, my wife, from a do, so will be starting him from totally cold for the first time since the ECU reset

Fingers crossed we have solved the problem......

Hooray for hopefully having fixed the problem, though boo for you having a wife.


One day Dave, one day...

Ucof said:

One day Dave, one day...

Click to expand...

I'll warn Sarah not to answer the door if you come knocking....

panda1408 said:

......My Panda was returning low MPG so I decided to change the sensor, when I fitted the new one it caused me alot of starting problems. When I tried to start the car it would instantly die, then it would take about 5-10 seconds of cranking to get it going again, it also died a few times when you started driving and would then refuse to start again. Sounds similar to your problem Ucof.

I did various ECU resets(as described in the Haynes manual) and tried another new sensor and the original, they all did the same thing(I did actually fit the wrong type of sensor originally so that may have something to do with it) In the end I had an ex-Fiat mechanic look at it, he diagnosed a broken vacumm advance, I changed that and then disconnected the battery for 10 minutes and it now starts fine. (Although the oil light now stays on after startup for a few seconds, which I think may be related somehow)

Have a look at the threads in the Panda section titled 'Low MPG' and 'Idle Speed CLX Inj'

Click to expand...

Hmmmm that sounds like what I have
Its as if even though it is the hieght of summer the choke is coming on??
I start it, rev it a bit, its often reluctant to do this, you floor the throttle and it just chuggs, then the revs eventually rise and its as if it clears its head and then runs OK

I was thinking this was a dodgy inlet manifold temp sensor......????
Telling the SPI the engine is cold and so the choke [cold start mode] comes on even though the weather is warm enough for the car to start without "cold start mode"....hmmmmm

Jo0Lz

jo0lz, sounds like mine issue, which happens to me from time to time.

Then, I start the car, pull handbrake, leave it running, and pull the choke motor (it has the part which looks like spring) with nail.

It makes hissing sound, and it moves to right position, and the engine immediately stabilizes. Then, I'm good for a period of time, after that, rinse and repeat.

'Choke motor' is located behind air cleaner, near screw for adjusting idling speed... Can't explain better with my English

I remember in the days of my old Toyota , one occasionaly had to tune/replace that wound up choke spring part. wonder if the same still applies to these new fandangled automobiles. Anyhow for cold start problems I'd start by checking vacuum advance. (this makes the engine idle faster by advancing the ignition), so if it is defective you may see the revs fall suddenly and hunt high and low. Its pretty simple to test, just unplug the long tube to the vacuum advance on the carburettor side and give it a bit of a suck to test if there is resistance on the other side. If it sucks air through like a straw, its time to replace... they realy don't last long, buy 2, the cars are getting older and spares rarer. They are only about 10 pounds each.