I have a 1.4 petrol. 62k on the clock.
About 4 months ago this car developed a very occasional misfire under load where the revs were on about 1800. Once the revs got higher the engine was perfect. I have lived with it since then as it only happened under predictable conditions - so sometimes I would knock it a gear lower and get higher revs to avoid the misfire.

What has happened lately though is that the car misfires all the time when I am pulling away at lower revs (this only happens once the engine is warm). Once the revs get higher the car is fine. I can drive for hours on a motorway with no problem - but the minute I then have to pull away from a junction it splutters under acceleration and then pirks up and drives fine - until you then have to pull away at another junction!

When the car is cold the misfire does not happen - only once it warms up.

I have tonight connected MultiECUscan and the only two codes present were P0300: Random/Mutiple Cylinders Misfire Detected
P0302: Cylinder 2 Misfire Detected

What should I be looking to fix/replace? I have had this car since it only had 11k on the clock and have serviced it myself regularly. It cannot be the spark plugs surely as the car runs so well at higher revs???

Does a 1.4 16valve have a coil pack which from what I have read is a common failing on its sibling - the MkII Punto?

Update:
Changed precat lambda sensor with a new one. It made no difference :bang:

Coil pack or coil packs... Googke your reg and type coil paxk, i had same problem on my stilo.

Thanks - turns out this engine does not have coil packs, so I might try getting some four ignition coils from the scrapyard to see if that makes a difference

tigershoot said:

Thanks - turns out this engine does not have coil packs, so I might try getting some four ignition coils from the scrapyard to see if that makes a difference

Click to expand...

STICK COILS.. built into plug leads.

Have you checked the plugs? I had a similar issue in my Pajero when I bought it and it turned out one of the spark plugs was cracked.

I changed the plugs but that made no difference. Thanks

tried running in the dark looking for arcing.

when you changed plugs were they all uniform in colour..??
if it's just 1 cylinder missing..the plug could / would have been darker..

tigershoot said:

Thanks - turns out this engine does not have coil packs, so I might try getting some four ignition coils from the scrapyard to see if that makes a difference

Click to expand...

:idea:buy 1 new one ( longest),
and then move it around the various plugs to see if the missing changes cylinder..or disappears.

Got three ignition coils today from a crashed Grande Punto as they are identical. Would have liked to have got all four but the number one coil was destroyed in the crash. Replaced coils in cylinders 1, 2 and 3 and the problem seems fixed

The plugs all appeared fine.

Hi,
I'm Andras from Hungary. I've visited here for a long time ago.
Veresecrazy, finally have you succeded to fix the missfire trouble by changing the ignition plugs?

THX for you reply, I'm fighting now with the same issue.
Regards,

András

Hello Everybody,

So, the trouble has started 2 weeks before. Engine hat not smooth run, on idling (800-900 RPM) started to get misfire. After checking the system with OBD II, fauilure codes are:
P0300 (red)

P0303 (red)
P0304 (yellow)
Ok, it means that cyl. 3 & 4 could have ignition problem. Let's debugging.

At the first shot, I changed all 4 of plugs. Old ones were a little bit dirty, a gap between electrodes was cca. 1-1.2 mm, so not so bad.
After change plugs, the misfire still exist.
A very expert "car professor" (and some websites, as my brain also) told me that misfire can not be occured by high voltage-coil failure, rather because of grounding by spark wires. So I bought and I'll change them today.
Results will be distributed ASAP.
Meantime, my Wife took the car here to a car mechanic, and he told she, it can be occured because of the breakage of cylinder head sealing-tear between cyl 3&4 !! Can U imagine, how does it any effect for the misfire?? I can't...

Thank you for any advice by Anyone,
regards
András

and photos here.

Hi,
seems coils are OK.
in any case when I changed the order of coils, the error code is the same.
(1-2-3-4 --> 1-2-4-3 -->3-4-1-2)
Tomorrow I'll change wires with connector blocks.
BR, András
(if somebody would have any idea, what should I do, it would be highly appreciated)

Hi,
Had a similar problem on my idea 1.4 when i first bought it,(kept misfiring and once cut out altogether with an engine fail light on) took it back to the garage where i had bought and it turned out to be the relays in the fuse box under the bonnet.
Not saying this IS the problem but may be worth checking.