hi, i am new to this forum so sorry if posted in wrong section,
last friday i was driving back from seeing my friend, and all of a sudden, the car just lost power, tried changing down the gears still no differance, aventuall got it to a stop at a layby, and it was still running but mis-firing, also when you reved it you could hear a knocking noise, luckily my mum was close by so i got a tow home,

when the engine is running, you can smell petrol really strongly, and the spark plugs are soaked in fuel, tried changing the single point injection unit but still no luck, now it won't start and the batterys flat

its a punto mark 1 1.2 8v single point injection

any help would be appricated thanks

Welcome to the club. these are things to first check and follow on when you know what's going on:

Charge the battery. While its charging -
Is there oil in the sump?
Is there "water" in the cooling system?
Is the oil and water clean. Watery oil or oily water suggest the head gasket has failed.
Also do a compression test to see if its blown the head gasket or seized and damaged a cylinder bore..

Also check the battery earth connections to the engine - just in case they are dirty.
When the battery is charged, if the engine starts put the lights on and see if they get brighter when you rev the engine above tickover. If they dont they alternator might be faulty and will need a voltage test.

one of the first things i done is checked the oil, and its fine, the water is also fine and the water and oil haven't mixed, i have tried jumping from another car to get it to start but still no joy, i will charge the battery tonight

D'Oh!!!

I forgot to mention cam belt. Take off the belt cover & crank the engine if its not turning the belts has stripped it teeth. Its an 8V engine so there will be no other harm done.

took cam cover off and the belt is turning fine, its not stripped teeth or anything, don't know if i mentioned it is overfueling seriously, what would cause that?
took out plugs to check there sparking, which they are and checked resistance of ht leads, which are 4k 5k 6k 4k, which i think are fine if my knowledge is right
anything else i can try?

Over fuelling can be a lambda fault, but it usually wont stop the engine. Looks like you need to read the ECU fault codes. There's lots of info on the forum via Google and Fiat Forum searches.

I would also suggest a compression test to rule out head gasket.

When jump starting (with donor engine NOT running) does your starter turn the engine at normal speed?

if there was any fault codes surely engine managment light would be on ?? or has it got one?

if the timming jumped, would this cause this problem?

It can be within "normal range" but still make the engine run rough. But as said unlikely to be enough to prevent it starting. The cam belt cannot jump (its a myth) but it can lose teeth.

Usually, when cam belt is ok starter makes a continuous hum/whizz. When the belts fails it goes fast/slow/fast/slow as some cylinders are compressing and some are not.

so what would cause it not to start now?

Crank sensor, immobiliser dead short within battery.
All guesses.
More information needed.

Mk 1 Punto's have a history of coil pack failures. From your original post, "Power droped - managed to crawl into a layby" I suspect you were limping along on two cylinders. The Punto has a dual coil arrangement. One coil feeds two cylinders, the other, the remaining two.
Have you taken all plugs out, and are they all covered in petrol. If two are dry and the other two wet, I reckon you are looking at a dead coil.
I have seen a new coil advertised for under £27, so not a major expense.
There was an excellent sticky on the forum on how to test a coil with the aid of a test lamp. Perhaps a Mod could point you towards it.

yeah when i was in the lay-by the car was misfiring. from what i remember i did take the plugs out and 2 were soaking with fuel and other 2 were fine , not 100% sure on that so il check again

Looks like Simples is on the case with the coil(s)

hey, just been out and had a look, all 4 plugs are sparking, part from no 3 is dull to non existant, tryied starting it then checked plugs and all for were soaked in fuel, the spark plugs arent the best and neither are the ht leads, so do you think i should replace them before start spending loads of money on it??

WhiteSei said:

Crank sensor, immobiliser dead short within battery.
All guesses.
More information needed.

Click to expand...

what other information do you need?

From here with no equipment anything we suggest is guesswork.
Fix the stuff that you can see isn't right then you have a chance of finding less obvious faults.

The sparks sound dodgy so they are the first things to deal with.

ok well going to replace spark plugs and ht leads tommorrow and take it from there,
if coil pack was faulty, would it stop working all together or would it work but just not to full power?

Its basically a high voltage transformer so usually its go or no go. Mk2s have a twin winding coil pack so both are replaced in one lump. No point speculating with knackered plugs.

ok thanks for help so far, il let you know how i get on tommorrow