hi all.
recently bought a '98 mk1 punto 85elx 16v, 2 owners, 88k.
nice tidy car, not new [obviously].

i think the guy i bought it off, jet washed the engine bay etc.
it was running fine for the first week, but now it doesn't.

it misfires on acceleration, in all gears.:bang:
it'll cruise fine [but underpowered], it idles fine.

i've clean all connectors, ht leads' coils etc.
but still the same.

any ideas what could be the problem?
[would be truly grateful].

Those are the symptoms of an HT misfire (gets worse under load). So, a simple thing you can try is to find a nice dark place, open the bonnet and, with the engine running, see if you can spot any sparks jumping to earth from the HT system. If at first you see nothing try getting someone to rev the engine a few times to put it under load. You don't need to rev the nuts off it - say up to 3000 rpm would be fine - and don't hold the high revs, but you do need to use large throttle openings to make the engine work.

If you do see sparks DON'T TOUCH until you've switched the ignition off! As you may know the High Tension side of an ignition system will be delivering in excess of 10'000 volts! It don't half make your hair stand on end! There are other things which could give this symptom but looking for earthing sparks is a simple first step and you only need your eyes as diagnostic equipment.

many thanks.
tried that.
one of the leads ''appears'' to have a hole in it.
arc from that to ground.

new leads and plugs ordered.

cclliivvee said:

many thanks.
tried that.
one of the leads ''appears'' to have a hole in it.
arc from that to ground.

new leads and plugs ordered.

Click to expand...

That's great news. Sounds like you've cracked it! Funny how very often the simplest solution works - and I know because, being a pessimist, my default position is to always assume the worst! At least then I'm often pleasantly surprised when the answer is easier and cheaper to sort than I at first thought!

At ten years old, if the leads have not been changed before, you've really done quite well and renewing them is probably a good idea anyway, even if they had looked faultless. Do you know when the plugs were last changed? As you're doing leads it might be a good idea to maximise the advantage with a new set of plugs. And have a careful look for contamination/verdigris deposits in the coil connections.

I'm not a fan of power washing/steam cleaning engine bays. The last one I did was our old '92 Panda Parade. She had developed an oil leak from her camshaft sprocket seal which left the front of the engine in a right mess. I cleaned down the whole of the engine with Gunk and washed it off with the garden hose before renewing the seal - it looked lovely! Unfortunately it took a week before she ran again! She would crank on the starter but gave no sign of firing up. A couple of days of fault finding as and when I could spare the time showed there was nothing wrong with the timing (I'd fitted a new timing belt when I did the seal), plenty of fuel being supplied but no sparks. Narrowed down to the crankshaft sensor. Spent a couple of days trying to source one cheaply without success. Then on the Saturday morning, sitting in her driving seat, thinking about what I might do and "talking it over" with her - I know, I'm totally nuts! - I twisted the key and she leapt in to life! I can only guess that water had been shorting something, either in the sensor or its wiring/plug, which had now dried out in the warm summer weather (and yes I had tried to dry everything with both rags and compressed air).

Commercial cleaning equipment uses really aggressive chemicals which can, in the long term, eat into ally casings etc if not thoroughly washed/neutralise. I always feel more confident, when buying a used car, if the engine bay is a little grubby with just the smallest traces of oil weeps around driveshaft seals etc. To me, that's an "honest" car.

Good luck with the new leads. Do you know about "Shop4parts" for Fiat spares? I have no connection with them other than being a very satisfied customer. Genuine or quality pattern parts at very affordable prices. They are my default "go to".
Regards
Jock

Hang on. I said 10 years old above didn't l? 2018 now - '98 car. Oh dear, that's 20 years?

thanks.
i bought some ht leads off that 'orible ebay.
they were completely wrong.
so had to go back.
have since ordered one coil and plugs.

since this last post.
ordered new ht leads, they were wrong, had to go back.
fitted new genuine fiat/ngk plugs, and one coil.

still the same.

i find it a bit daft that they don't have an obdII connector.
anyone local to Junc 12/13 M25? able to give me a hand? please?

Ah well, some you win, some you loose! So sorry it wasn't the simple answer. Do let us all know what it turns out to be won't you? - hope it doesn't involve shed loads of money.

hi again.

right, after 1 set of HT leads that were wrong [returned].
new spark plugs fiat/ngk [good stuff].
1x new ign coil [prob didn't need]
another set of ht leads [they fit, but aren't the correct ones].
problem solved.

no more misfiring.
but..........
as i'm driving it, every now and then, a dash light [looks like an injector] pops up, and then goes out.
it doesn't bother me too much, as car runs sweet now.

any ideas how i can reset this code, and turn light off?

thanks.

cclliivvee said:

i find it a bit daft that they don't have an obdII connector.

Click to expand...

EOBD wasn't mandated until 2001, the Mk1's do have various diagnostics ports, but they need special adaptors to use. MultiECUScan 'should' work, I'd be inclined to give the guys at Gendan a call and see what adaptors, etc would be needed as the website package finder only seems to list the Punto 75.