A simple test with the multimeter will give you the answer
See;

slimfastjohn said:

Mine is firing on 3. Doesn't seem 2 b a spark on no. 3 cylinder. I've replaced spark plugs and switched them between cylinders, but it's still not firing on same one. I replaced the HT leads yesterday and no difference. Mine is a 1.4 bravo (yes I know) and so has 1 injector for all four pots so I kinda think that eliminates the possibility of a faulty injector? :bang:Is the coil the only option before an ECU? I ask simply because of the earlier post (quoted above).
Please help!!! (The fella I car share with for work is gettin a pissed with having to drive every shift!)
Thanks in advance, John

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Thanks Adrian will try when it's light. lol. Let u know how I get on!

Tested the Coils as above. all seems to be ok. What's next? ECU? Is there a test I can do on this before messing with it? Also, if I need to replace the ECU, is the fact I only have a blue key a problem??? =[

The ECUs are very reliable if the engine management light is not on it is probably not broken. The ecu sends two ouputs to the coil, one for the spark on cylinder 1+4 and one for the spark on 2+3, if your engine is constitantly running on 3 cylinders the two ECU signals must be reaching the coil pack. Maybe your getting a wasted spark because of one duff sparkplug on that shared coil winding.

You definatly have fuel.
From a spark point of view the coilpack tested ok, new leads, just spark plugs left to try.
Compression is an unknown at the moment.

I think new spark plugs then a compression test. NGK BKR6EKC are one correct spark plugs for the 1.4

I switched plugs to test em, before doin HT leads. Same cylinder not firing. There is no spark at the end of the HT lead- with the caps removed (one at a time obviously) each one will spark to the engine except the one that's not firing. yes there's fuel getting through - plug is wet if I check it just after running the engine. Probably worth mentioning the engine management light has come on a few times whilst driving. Not every journey and not consistent to long or short journeys etc. Just comes on for 10 - 15 min now and then! (sorry for not mentioning that one b4!)

Another thing, I've read on the net about resetting the ECU by disconnecting the battery for a min of 45 minutes then leaving the engine to tick over for 5. thinking about it, the problems I had with it running were after the missus left the stereo on overnight and totally drained the battery. Dunno if this could've triggered something or it's just coincidence???
(I'm gonna try the reset when I'm off work 2moro morning- I'll let u know if any change). =]

Tried. tested. FAIL. =[ Any ideas?

ok, so I got a coil pack off a scrapper this morning. £12 (should've been £20 but told him only had £12 lol). Put on, but made no difference to the tick over revving a little then almost dying over and over. It ran fine and seemed to be back to full power whilst accelerating, and didn't cut out when slowing down. Tried again a bit later and its back as it was before changing the coils. Could the ECU be to blame? Is it knackering the coils? Also, (just to check) I switched all the HT leads around ie 1-4 2-3 3-2 & 4-1. so all are on different plugs, and it made no difference! not even a little worse! AAARRRGGGHHH!!!!! HELP! PLEASE! Scrapper wants £60 for an ECU (inc. 2 blue keys) but is it just money for old rope if I can't be sure that it'll work? The car was only £400 in the first place a few months ago, should I just buy something else?

hi mate seems like your having the same problem as me its doing my head in now
ive changed plugs and leads and am buying a new coil pack tomorrow for £26 see if that helps me.
one thing that might apply to you also is someones told me my problem could also be the "crankshaft sensor" as a faulty one may give similar results but apparently if it was that the car would run alot better at certain revs in each gear.
ive read yr other posts about testing the coil pack im a bit puzzled on how you did it .

did you just put the tester into the coil pack pins 1&4 and then again in pins 3&2
if you do leave the battery off to try and reset the ECU from what i remember its important that when you first restart the car after reconnecting not to rev the engine for about 5 mins as it needs to register something on the ECU ,thats from what i remember i may be wrong lol

hi sorry to ask you things in yr post
but ive figured out how you checked the resistance but did u do it when the engine was running or turned off?

Unless you want a few millions volts running through your volt meter, and turning it into a mound of molten plastic dripping over your hands, TURN OFF THE ENGINE!!

Just think about what you are measuring here and what it's function is! (Trust me, several thousand volts hurts like a bitch if you're lucky. It'll stop your heart if you are not)

(The melting plastic bit might be a bit exaggerated but it WILL ruin your voltmeter and possibly your day if you try measuring the coilpack with the engine running

thanks for that didn't think there would be much voltage in the connectors that's all lol
Hope you guys have better luck than i am having had similar problems like i said i have now changed the plugs,leads,Coil pack and still the same ,if you guys do fix it please post on here what was up so it might help me lol
if anyone can help on mine also ive got a thread also
https://www.fiatforum.com/bravo-brava/292214-brava-1-2-sx-just-started-mis-firing.html

Lol I've just realised I posted in a thread that was a few years old gotta remember to check dats first lol

Hi have y plate punt Mia warning light came on intermediate cutting out and no power in reverse cleaned air filter n hoses then next day driving the same if not bit better still had no power in reverse then it started to cut out again wen going into second thinking could b coil heard there's a secondary coil one coil firing 2cylenders can get both coils for 20 pound but want to b sure before spending money just had new battery n starter fixed so think can eliminate them. Any help appreciated. Tnx it's a 1200cc

New to forum can someone pm me or reply on screen don't know how to retrieve replys

Hello,Jugs.Re : this old post of yours:re: Should not test HT leads. I have checked the resistances several times on my 1994 899cc Cinquecento ,recently purchased . I have readings on 20kohms setting of 0.5 0.45 0.2 and one lead has 3.73. Yes I could just replace the leads but I would like to know which ones are faulty as a learning experience. Is there a reason why the leads should not be tested? What are the correct resistances please. Thank you ,Cinquephil175.

The resistance of HT leads is so high it's hard to properly test them with a normal Ohm meter. So you never know for certain if a lead with a high or low resistance actually HAS that resistance or if there was bad contact between one of the probes and the lead.

Also, HT leads don't have a fixed "correct resistance". It varies from lead to lead and brand to brand. The resistance is not really of that great an effect on the ignition so long as there are no internal breaks or worn insulation. (Another reason why you can't really test them in the first place)

HT leads are relatively cheap. If you suspect one might be bad, it's better to just replace them. If one wasn't bad already, one will go bad soon. So by replacing when you suspect they MIGHT be playing up you avoid trouble later.

Rob666 said:

I had this prob on my 1.6. pot 1 wasn't firing and blew my ignition pack. after going through a (so-called) automotive electrical engineer who told me that my leads where fine I ended up replacing the coil pack, ECU (I know), plugs and eventually found out that the leads connector, where it attaches to the top of the plug had failed and the lead was shorting on the block, boiling the ignition pack! needless to say the electrician gave me my money back and paid for half the new ECU. At least I know I've got a new electrical system in the car now. so Warning to all, check the leads and the plugs electrically and physically first before taking it to a garage.

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I'm confused which lead failed? The one that fits on to the top of the spark plug ?

deeinlondon said:

I'm confused which lead failed? The one that fits on to the top of the spark plug ?

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This thread was originally from 2012 you likey won't get a response now

I've had the same car for the last 18 years - I may or may not - but it don't harm not one to ask