I have just acquired a 1999 1.1 Seicento Sporting SPi.
It has 22k genuine miles, but has sat for 3 years (elderly owner died) - not sure how much of that with a flat battery.
I was told that it was a non starter, they had tried to jump it, and that it had probably forgotten the key.
Put a new battery on it and put in a gallon of fuel.
Turned key - code light came on and went out as it should, the injector light came on for about 4 secs and went out as it should, cranked it and it Span, oil light went out - not even a cough.
Went under the lid and have given it a good going over, checked every connection I could see, all seemed good. Checked every fuse - including the ones behind the battery. Took a plug out and tried it on both coil packs - cranked - no spark. Looked down carb and had a sniff - no hint of fuel. Seems to hint at crank sensor, fuel cut off and/or suspect coil packs - all could add up to quite a bill if I replace them one by one then find the ECU up the swan.
I have ordered up the 3 pin adapted and the OBDII adapted from eBay and hope to get some kind of hint back on my laptop.
I checked the coil pack resistances both same (from memory either 3.5k or 7.5k didn't commit to memory, but both the same)
I put a 12v test lamp on the 12v to the coil packs to the -ve battery, lamp on for a few seconds when ignition turned on then goes off (a large relay pack next to the ECU clicks in then out at the same time - when it goes off the coil power goes off). Put test lamp to +ve battery to coil pack trigger - cranked engine - no light.
Disconnected crank sensor, helper cranked engine - dabbed end of test lamp lead rapidly to crank sensor input pin and occasionally seemed to inject fuel.

Can anyone confirm my initial guesses and/or come up with a way to reliably test ECU 0v triggers to coils. And tell me where the fuel cut off is an does it kill the spark?

(I am a sparky by trade, and am now a controls engineer - love classic cars and have had many projects - this is my 1st fly by wire! Give me a carb & dizzy and I am happy as a pig in muck! - try to earn Dad points with my 17yr old daughters 1st car project!)

Update - came across some cheap new coil packs (value not quality!), swapped them - still didn't start(surprise!!! Not!!!), I need to keep away from car spares shops! (Finding it hard to resist a crank sensor �&#56876
Also found the fuel cut-off reset behind the dash - also no start after pressing it.

Does anyone know if the Rev counter would flicker when cranking? Mine doesn't???

HI Spitie and welcome.

First off, from what I recall the rev counter doesn't move until the engine actually starts.
What you've suggested does point to crank sensor from my experience, pop down the scrappy and grab one. If it fits in your pocket, it's free

Eklipze3k said:

If it fits in your pocket, it's free

Click to expand...

And i have big pockets....

To be honest, new crank sensors aren't too expensive on Ebay, worth a look,

Thanks for the pointers. Tried a couple of scrappies - doesn't seem to be a common car in breakers, loads on eBay but decided to get one local - 5 mins to fit then vroom?
Looked in the tech manual I downloaded from the downloads section, it says that all of the other sensors will bring on the ECU lamp and substitute a known value and give you a lamp and limp home mode. The only sensor that the ECU can't substitute is the crank sensor and so will prevent fuel delivery and spark.