Hello Guys
I own a 2001 Fiat Seicento Sporting. The problem I'm having with it is a misfire. I do have a light up on the dash (orange one just below where the picture of a key comes up)
From the start... about 6 months ago it develoed a misfire on startup, it would fast idle and then drop very low in the revs but with a good rev it would go back to normal, sometimes the light would go off, sometimes it would stay, irrelevant of how it was running. sometimes though it would be completely fine for fairly long periods. as it was intermittent I just carried on driving it; but it got a lot worse, the periods of time it would do it for increased slowly until as it is now which is constant, in all conditions all rev ranges even without load. A friend has used a diagnostics unit on it, which reads, coil pack A malfunction, (or thereabouts, cant remember the exact words).
So; i changed both coil packs, to no avail and assuming it would be something to do with ignition for it to read this fault I have also changed leads and plugs. whilst doing so upon visual inspection I could see that cylinders 1 and 4 are clearly not firing properly, however, all are sparking correctly when outside the car. The input from the loom reads a steady voltage Into the coil pack. I have checked every earth i can find and cleaned them up, and visually inspected all sensors etc. One other thing that I have literally thought of as quite odd for a misfire is that I can't actually smell any unburnt fuel whilst driving it.
After reading through you forums for any similar posts, one has come to my attention which appears to be very similar posted 02,12,09 by Rush titled seicento sporting intermittant missfire.
Any Ideas as I'm totally at a loss
Thanks guys

Try the Lambda sensor.
My old Sei had the same kind of problem. And I went thru the same things you have. Turned out it was the sensor was on it's way out.
Got it replaced £80 and that was including parts and labor

There is an issue with early Sei Mpi ecus, the coil drivers can fail.

Get a proper diagnostic done to confirm.

Cheers

D

Thanks guys for you responses, I was thinking along very similar lines, the only thing that swayed me more towards coil drivers is that I wouldn't have thought I would have the light on in the dash if the lambda were going; how similar were your problems?
On the note of coil drivers, in terms of a repair; what options are available? Prices etc?
Presuming this could be an expensive job and I would potentially have to have the car off the road for a period of time, if I were to replace the ECU what do I need to consider? Would it be along the lines of code box, ECU it's self and maybe a new ignition barrel? Would a basic unit reset, which would most likely have taken place anyway upon removal and transport, be enough to just swap the units and go, or, is there any programming to consider? and also is there something which would have caused a coil driver failure external to the ECU or is it the components themselves?
Cheers

ECU doctor does repairs by post, I understand its only a couple of days, and its plug and play thereafter.

Any change is going to need the code box and chips for the keys.

Cheers

D

Thank you greatly for your help very much appreciated
cheers

My symptoms where more or less the same as the ones you're describing.
The continued after I had new plugs and leads. And after many other tinkerings and fault finding missions. It was someone here who suggested Lambda. Took it to garage, asked for Lambda to be replaced, £80 later and no more surging/mis-firing.