General UNO 1.1 i.e. idle problems and iar leacks

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General UNO 1.1 i.e. idle problems and iar leacks

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Oct 1, 2004
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Hello to everyone! My car continues to have problems at idle (mono jetronic bosc). When it's cold it works fine (mixture is probably enriched by ECU and I also see throttle position opens a bit through the stepper motor), but as soon as it starts to warming up, idle returns to its default level and engine starts to run rough. This problem is very evident after the first 2 or 3 minutes of working and it diminuishes when the engine is completely warmed up. During this summer and this autumn the problem disappeared with engine completely warm (coolant indicator approx at central values) but now it is present continuatively. In particular if I stop the car for any reason I can listen the idle r.p.m. to diminuish and then it is incremented. If I accelerate and then I relase the accelerator I see the same problem. If I leave the car at idle for a minute, idle is correct but sometimes it diminuishes without reasons. Sometimes the engine cuts out. I did a lot of checks, I also changed coolant sensor and vacuum advance but the problem still remains. I checked Lambda voltage and it's correct when I go on road pushing accelerator with a gear (it changes rapidly). But Lambda voltage is very low at idle (0.1 - 0.2 V) and sometimes it rises up to 0.7 0.8, then it diminuishes another time. Idle problems start when lambda voltage is low. SO I' m sure that it's a problem of LEAN MIXTURE at idle!!! But I can't find any air leacks... where I can search for some air connection loose or similar? Or what can cause this lean mixture only at idle? Engine works fine an all the others working conditions!!!
 
Re: UNO 1.1 i.e. idle problems and air leacks

There's a mistake in title... it's "air leak"!!!
However... does anyone knows what could be happen in my car? It started really to annoyng me because sometimes engine cuts out and probably some uburned fuel can came inside catalyzer, blowing it. However I put injector cleaner in fuel, I changed water temp sensor and changed vacuum advance without results. Please help me in this trouble, thanks again, Andrea.
 
Re: UNO 1.1 i.e. idle problems and air leaks

There's a mistake in title... it's "air leak"!!!
However... does anyone knows what could be happen in my car? It started really to annoyng me because sometimes engine cuts out and probably some uburned fuel can came inside catalyzer, blowing it. However I put injector cleaner in fuel, I changed water temp sensor and changed vacuum advance without results. Please help me in this trouble, thanks again, Andrea.
 
UNO 1.1 i.e. idle and Poor charging light

See my post on Battery lamp always lights (a few)
icon4.gif

https://www.fiatforum.com/showthread.php?p=208411&posted=1#post208411
As there could be an alternator link.
Also, what are your Air Cleaner rubber "feet" like, Mine snapped off and I replaced them with the end of a Bic Biro. I don't think it matters though.
Louie Bee.
 
Hello! Thank for your reply!
Sorry but I did not understand what do you mean with "Air Cleaner rubber feet "... I can't imagine anything which is substituting with a BIC biro end in the air filter zone ^_^ !
 
Sorry to keep jumping between threads, But from

https://www.fiatforum.com/showthread.php?t=18879

I quote andre79ge :

“I did not completely controlled vacuum advance hose because it goes under air filter/injector groups and so I could not check it completely. However I checked the "power" of its vacuum by putting a fìnger on its hole and I could feel the vacuum (it is high at idle and it diminuishes by doing a hard aperture on throttle position, I think it’s correct). So vacuum is present but I can't be sure that that hose is completely OK. However I think that it's a very poor and almost negligible air leak because the vacuum is good!”

I think you are right to rule out a link to a poor alternator/idling problems. If the battery was getting too low, the battery would not be holding enough power to restart car, and drawing more current (headlights etc) would prob then make the engine idol worse (was a bit late last night – sorry)

I think (90% again) the 1.0IE and 1.1IE have exactly the same distributor and SPI setup (maybe a different ECU) with white distributor cap. On my 1993 1.0 (IE) the Vacuum hose runs freely around the engine (not over it) to a right angle connection on the back of the throttle body.

I am guessing but I think your hose is rooted wrong. It could have had bad parts cut out in the past. Perhaps then it was rerouted taking a shorter path. If so, the chances are the pipe will have perished more. If you have disturbed the air cleaner (eg. when looking at injector jet) it may now be squashing and blocking the pipe preventing the vacuum advance functioning correctly (as would bigger nicks and holes). It might be worth trying the pressure at the other end of pipe. (With engine off), unplug pipe from the throttle body and free it from anything else enroot to Vac` advance. Try pressure by sucking and blowing down pipe. If pipe OK and no signs of pipe collapsing inwards see if it can SAFELY reach round engine (anti clockwise) to the throttle body. I am 90% sure your root incorrect if you have a white distributor cap, but FIAT do change things. Let us know if your current root is correct with a different connection point to throttle body for 1.1 IE, or how she idols from cold with new (Correct?) configuration.



Air Cleaner Rubber “Feet”

If you remove the air cleaner box (not the part bolted on to the throttle body) and look underneath (where it rests on the cam cover) there should be 2 little round bits of rubber sticking out the air cleaner box. I call these the “feet” which are about 5MM deep. With age they perish and brake off leaving behind hole(s) in the bottom of the box (just smaller that the x-section of a biro).

Air can whistle through the hole(s). Box may rattle against the cam cover (no damping) and extra vibrations would travel along to the throttle body bolt and gasket. As this stage is before the air filter I guess its not too bad as any dirt sucked in will be filtered (shortening the life of the filter). I replaced both feet from scrap yards after a good search they were missing from most UNOs (like the emergency jack’s rubber feet).

One since broke off again, so I snapped off the end on a round nylon Biro (the ball end) about 30 MM long, filed it down till the right depth sticks out when plugging the whistle hole (from the outside). Oh shoot, maybe that’s why its injection badge started to rattle after changing the filter – nylon has wrong damping – sorry It takes a long time to think through and longer to type (in Word) and re-think / type (You’d never believe I am dyslexic? – Probably would) It was only a temp measure and seemed fine with old filter (goanna get a proper foot at weekend).

What is your hot/Cool air intake thermostat like? Someone had fitted mine with a plastic (hand cut) washer before the fixing screw. It was rattling around inside the air cleaner. I fixed its “mountain” thingy by winging plastic tape round the plastic gasket, before screwing it back in (and throwing the extra washer out).

Then on re-assembly the little Hot / cold air intake flap snapped off (the thermostat connected was knocking against it since who knows when so it was stressed). I managed to tap a pin in to the flap remove it then force in a little screw then fit it back together (fiddly robot parts). Then I tested the thermostat by poring boiling water over the metal thermostat (over the sink) as it warms and expands, it pushes the flap downwards so to cover and block the hot air intake path (air too warm). Pressing Ice on it cools it, so thermostat contracts till the and pushes the flap upwards to let more and more hot air in till it blocks the cold path completely (cold start). This only shows it is operational, but I don’t know if it is set properly (original angle of flap on connector unknown)

Louie Bee
 
Finally my grandfather had... I don't know how to say it in English, however he went with my car on another car crashing both of them.
My car had an external light broken (both glass and supports), engine cover (can't explain it with the correct word, however it's the cover that you have to pull up if you want to see engine's zone) and also "front bumper" (the black/brown plastic part in front of the car) and lateral chassis (over the left wheel). So my parents decided to leave the car and take a new one because technicians want one thousand euros for repair it...
Not happy for this decision!!!
I' m starting to think to repair it by myself, buying chassis parts by second hand in order to get them cheap!!!
So I can't say anything new about idle problems and battery charging.
I hope to have the possibility to take another look on that problems. In other words... I hope my parents don't decide to completely demolish my old UNO!!! I like it a lot...
Hope to reply on this forum another time...
 
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