Ford Fiesta Zetec Lx 1.25 - 2000 Misfiring At Low Revs

[andylovell]

Hi can anyone help?

My ford fiesta 1.25, 2000 model is misfiring at low revs. I have replaced the HT leads and spark plugs but it still misfiring at low revs and only when the engine is warm.

The garage has checked it and cannot find a problem except from a slight hesitation at accelerating hard, they believe its the coil pack but cannot be sure and as its £100 it could be a waste of money.

Has anyone else experienced this problem if so do you know what needs to be replaced or cleaned?

Many thanks.

[Dai84]

I had this problem with my fiesta last week mate, I changed spark plugs too and that didn't work. Eventually took it to a garage and it was the coil pack. This is a very common problem on these cars apparently, my garage quoted my £60 +Vat for part and fitting with 12 month warranty. However, it might be worth getting one off eBay for around £20 - £30 and fit it for yourself if your a "give it a go" kinda guy like me?! Or if u know anyone with similar car, u could try using their coil pack to see if it is the problem part before forking out money, or ring your local scrappy/breakers yard?

[Dai84]

http://www.ebay.co.uk/sch/i.html?_trksid=p5197.m570.l1313&_nkw=Fiesta+coil+pack&_sacat=0

[andylovell]

there were no issues on the computer when it was tested after the spark plugs and ht leads changed.. was it the same for you? and also was it ONLY when the car was warm?

[Dai84]

The mechanics found the appropriate error code when they plugged her in, which showed up that the 1st cylinder was misfiring and then tested the ht leads which were fine, so the problem was traced bk to the coil pack. My car was basically mis firing from cold and warm, basically all the time! When idle, the revs were up and down all over the place, exhaust sounded dodgy, car was shaking and basically sounded like a diesel......yuk! So although it doesn't seem like the exact problem that ur having, I think that replacing the coil pack (preferably with someone else's) to find out if that's what's causing u problems is a quick, easy and cheap way to find the cause by process of elimination, without going to a garage and then being told there is nothing wrong when they plug it into an obd reader, and then charge u 30 quid for the pleasure!

Does seem strange that no error codes are coming up tho. Have u noticed any lack of power since this happened?

[andylovell]

Hi cheers for replying again.

It started misfiring at all revs and was virtually undriveable. Anyway I told my dad and he said it could be the HT leads so we changed them over beacuse they were knackered but it carried on misfiring. I took it to a garage (a small one not like kwikfit who charge £30 just for checking!) and they found the spark plug were all rusted (caused by a broken seal) I was given it back and did 2 miles in it and it started again, took it back and they found nothing apart from this slight hesitation on accelerating.

Now i took it out again today and it's possible to ignore it by say taking her to 3.5k revs then changing gear but if you change at 2-2.5k revs it judders, is it worth getting it sorted i dont know? its only through heavy acceleration and/or labouring engine.

I must stress it is only intermitterant and before the spark plugs were replaced it was constant but again only on a warm engine.

[Dai84]

If it doesn't bother u then it might be worth postponing it for a while, but if it is mis firing then u are gonna notice a reduction in fuel economy and performance. I'm certainly no mechanic, but I forked out 20 quid for a haynes manual and now confident to do some amateur repairs and servicing myself, such as coil packs, fuel, air and oil filter changes. And I've no idea, but it could maybe cause further problems down the line with cat converters etc, if the engines mis firing, then not all the fuel is being burned!

[andylovell]

oh okay cheers mate, it really does bother me but i guess its gonna have to be done before i sell it on or just let someone take it on a very very short test drive....

thanks again mate ill give it a shot and get back to you if its been fixed!

[Fenners]

Hi All first post on here, just bought a new fiesta ztec 2010 last week and mine has started with this, so took it back and they said it was a miss firing piston so it's booked in the ford dealership thursday, its juddering at low speeds and the wheels aren't balanced as its shaking at high speeds.

[andylovell]

if its any consolation my fiesta has always suffered from a shaking steering wheel at any speeds above 65mph, although it does seem to get slightly better above 80mph.. work that one out?

[andylovell]

A tank full of fuel and redex later has seemed to have fixed the problem! The fuel line must've been clogged up with dirt.

[BLOOMIN-CARS]

some misfires are not always to do with plugs, coil packs n leads.... u need to check round the air hoses, especially if you have one of those silly valves in exhaust manifold onto a rubber pipe which goes to the inlet. they are prone to going soft, sucking in on themselves and then splitting. have replaced loads of them after cars have been to garages for 'hunting' 'misfires' and general idling problems. everyone seems far too keen to chuck a coil pack on and yes a more powerfull spark might make it better for a day or 2, but then problems generally come back if there is an air leak.

i have seen many many people waste fortunes of money changing sensors which they did not need to, all because of a rubber pipe, that is aroun 10-15 quid from ford, or 50 pence worth from local motor factors. no clips to take off, just slides on, 5 mins later.. jobs a good un.