misfiring intermittently, also engine warning warning light coming on now and again. Runs okay for a short period and then starts to misfire.
Have changed coil pack, ht leads and plugs, was okay for a few days but problem has reoccurred today and started to misfire and engine warning light on again.
Please help, any ideas as to what this could be?

Dennis O'Callaghan, April 2008

i have the same problen on my mk6 53plate would a leaking core plug cause the car to smoke when reeved high

mark, April 2017

Hi there, I hope someone can help. A couple of days ago I was driving along with my mum and all of a sudden my door light on the dash little up and the centre light (one that comes on when you get out the car) further on the oil light came on and the engine started to misfire and sound choked. Got out and checked my oil incase but was fine. Tried to make it home but the engine was just severely losing power and I was driving downhill. AA picked me up plugged in the diagnostics and came up with the lamba sensor which I already know about, he seemEdd to think a blocked exhaust like the cat collapsed however also as I pulled in the indicator acted like it had a bad earth clicking really fast. I got it towed home and 2 days later I decide to try start it.. it did with no problem and I drove the 5miles to work and back without fault. Yesterday tried to start it in the morning, ran fine for 5 seconds the centre light and open door light on the dash came on and engine started to act starved again. Please help if you can! Thanks.

Zanderpander1010, November 2016

hi every 1 the answer you are looking for is you need 2 clean your throttle body or replace with a new 1 and all so the maf air control module to air box these componants cause car 2 misfire and poor idol and lack off power when driving. sort these 2 items out an your car will drive smooth and responsive like it should. as for the leaking jet wash this only causes damage 2 spark plugs leads. the parts are easy 2 fix and not 2 expensive 2 get garage 2 sort out if you are not able. reason throttle bodys wer and become dirty sometimes cleaning them can work but its best 2 sorce new guarantee this will fix your problem.

wayne, December 2015

I've got same problem Misfire on cylinders 1 & 4 no spark the RAC guy trued one of there coil packs still the same he said suspect ecu not switching but I found out that a ford Fiesta MK6 2003 on wards suffer a inherent fault with the washer jets on the bonnet as thy leak in rain & water funs down on cylinders 1 & for coursing a fault as when I took the plugs out two of them were covered in waster & two plugs were rusty car going to the garage tomorrow as now I don't trust the RAC & I've all so bought the upgraded washer Jets that don't leak I'll replace them as soon as thy arrive

Michael, December 2015

same problem 1.4 2003 fiesta mk6 , had new plugs,leads & coil still misfires or sluggish , doesn't like to rev high , going up hill can be poor if there are a few people in car , so annoying , ok on flat in 4th and 5th gear , 1st 2nd 3rd poor pulling off and hills , HELP

ross, November 2013

Hi i have just bought a 52 plate (2003) ford focus 1.6 zetec (petrol) have just had a power steering pump fitted as the original wasn't working the engine management orange light stays on and loses power when driving the bloke told me who i bought the car from the orange light is on because of the faulty steering pump, and now know this is not the case
any suggestions thanks

Colin, October 2013

My 2003 1.4 Zetec has recently developed this misfire problem. Engine management light came on took it to garage which threw up a CAT deficiency. Changed the CAT and running like a dream again... Hope this helps

Mike, May 2013

Our 2003 1.4 Fiesta developed a misfire then went to run on 3 cylinders. When I investigated this the spark plugs were rusty! Water gets in from the windscreen washers and runs down in between the 2 camshaft covers on to the spark plugs causing the coil pack to short out. I replaced the coil pack and made a cover to stop the water dripping from the windscreen washers. I need to get the later windscreen washers. Car had done 35k when this happened.

Rob, October 2012

I had a simular problem - changed everything twice. The solution was a leaking core pug in the head. There are two - one each end letting water through onto the plugs. Remove the cam cover and take out the offending core plug and reseal it.

Brian Davies, June 2012

I have this problem on the 1.2 ive taken the plastic cover off dried off the water from around the plugs and run the engine if you look closely you can see the water coming back up from the core plugs/frost plugs but you have to look closely on some cars you will see it coming back on others you wont as the problem will not be as obvious.

jaguar, March 2012

Hi all
Same rusty water / misfire/ engine warning light problem with 2003 1.4 zetec. Been to garage without success. After completely sealing windscreen washer outlets, during heavy rain eventually noticed water tracking under bonnet and dripping on airfilter cover immidiately under driver side windscreen washer outlet then down onto engine. Found cause to be washer hose was unclipped from bonnet on passenger side and rain was running down this then across inner bonnet.

Trevor, September 2011

have owned this 2003 fiesta 1.4 zetec 1 month, right from the start seemed to be holding back, lack of oomph. drive it fast seems ok but drive it properly and it sort of struggles not a misfire as such just lazy and hesitant moving through the gears, just not smooth.
my other 1.2 fiesta zetec 1995 knocks this one into a cocked hat.
so far the garage has renewed x4 plugs coil pack and x4 leads so all the issues with damp plugs and stuff should have gone but oh no it still doing the same. is there nobody out there that has an answer sounds like such a common fault on such a common car.
please please help whats next..............
so much for technology hey!!

ron, August 2011

Hi.. you can see there's a variety of proposed answers - here's my experience (Fiesta 1.4 Zetec 2004).

- 35k miles : misfire at high revs; on inspection i found rusty water around spark plugs and i immediately assumed this was leaking core plugs and had these replaced...in error
- 40k miles : problem reoccurred the following winter and i found that it was the washer jet sealing as mentioned elsewhere; should've realised first time as water was rusty, not antifreeze coloured
- 60k miles: really serious misfire on light throttle which turned out to be the coil pack and not connected in anyway to water

- 65k miles: blown head gasket, broken front coil spring (all joints/nuts seized making replacement a nightmare) and starter motor not engaging...all occurred within 50 miles of each other. Not a good advert for Ford !

Jon, June 2011

Found my problem to be one of the 2 core plugs or also known as frost plugs to be leaking. These are located between spark plug 1 & 2 and 3 & 4. They blow if engine freezes. Screwed in with hex key.
Could not get plug out, tried Block sealant fluid, Lasted for about 2 days then blew again.
Replaced £3 plug and leaks stopped. Huge hassle getting plug out ended up drilling and chisel.
Sealed new plug with copper gasket sealant and nylon threaded PTFE tape. Still going.

Sandy, March 2011

Yup Washers all the way, had this issue on my friends 1.6 2005 Focus, water sitting all around the plugs which was caused by water running through the hole in the bonnet designed for the washers and onto the camshaft cover from there it then leaked through a rubber bung between leads number 2 and 3 thus filling the spark plug well with water causing ignition faults and engine management lights coming on. our solution was to drill a hole in the rubber bung and put a 1 inch piece of hose through the hole then seal the rubber bung with sealent (hylomar blue in our case) this stopped the water leaking into the spark plug well. It solved the problem and also allowed any moisture that got into the spark plug well to vent out through the piece of tube. Later models came with both rubber seals round the washer jets and no rubber bung on the camshaft cover, they just continued the plastic moulding therfore covering the hole. After speaking to quite a few people involved with fords, they said this was most common of fiestas but as we've proved is also prevalent on focuses of this age.

Ross Codrai, February 2011

Hello all, I have the same problems engine warning and limp home mode, went to change spark plugs and found them to be flooded with water. but the water is deffintley is coolant as its is red/pink not rust. Anybody tell me where it may be leaking from. Have been topping up coolant for months and now no where its is ending up. Been checking oil cap to see if contaminated but it is not.
Would this be the cylinder head gasket?

Sandy, May 2010

Remove the cam position sensor from the rear of the rocker cover and give it a good clean. It is positioned on the top left hand side of the rocker cover. Hope this helps.

Steve, April 2010

having same fun on a 1600 auto style changed plugs/ht leads/coil put fuel cleaner in new fuel filter .mine is bad when cold first strted but is ok when warm tho it fells a bit rough worst when wet or forsty night?????????????????

ian graham, March 2010

usual problem of under revving or holding back is problem with cat converter

tony, January 2010

when im idle and rev the car it missfires but doesnt affect the driving i dont think sluggish pulling away from a roundabout for example in 2nd or 3rd juders.... changed the plugs should i change the ht leads??

harry, September 2009

did anyone solve this i have got the exact same problem me to have replaced coil pack, ht leads, and spark plugs had engine warning light taken off few times no one seems to pin point pronlem any ideas b4 i go to ford

jamie smith, September 2009

had the same problem missfiring and struggling under load. changed the leads and all was cool. if it has had a lot of water round the spark plugs it wise to change the leads and plugs, my old plugs i took out were rusted down the center really bad. i also spoke the the ford people and they told me the the washer jets dont have a rubber seal round them, so when it rains the water passes round the jets, on to the air box and down some how ending up round the spark plugs. so they have modified the washer jets with rubber. have just fitted them now so hopefuly problem solved!!!!!!

chris, May 2009

Any1 fixed this problem yet? i have changed so far, plugs, leads, coil, got rid of the missfire but the cars is idleing funny hunting up and down and cuts out after you rev the engine (sometimes just manages to stay going) and seems slower? ant ideas????????

Andy G, April 2009

i am having the same problem i have changed the plugs and it was running ok now its seems to be misfiring very little when stationary also when put foot down i have a 2002 mk6 1.4 zetec and its doing my head in their is no warning light on yet can anyone help.

lance, December 2008

I have a similiar problem..

Fiesta 1.4 2004

It suddenly started run rough & engine warning light came on, called RAC who said it showed a fault on CYL 4. Turned out to be coil failure so I replaced coil/spark plugs & ignition leads & whilst it's much better it now seems slightly hesitant during acceleration sometimes..

my thoughts are maybe the fuel filter or the MAF / Lamba sensor have been affected by the coil failing ?

All advice appreciated

simon

simon, August 2008

Hi i am having the same problem can you tell me if you have rectified it?

Cheers

Sam

sam, July 2008

I had the same problem as well. it is the Lambda sensor. The Ford fiesta have two, they will both need replacing as i replaced one only the first time and the problem kept on persisting, so i changed both of them and all is running fine and its been a couple of months now, so have a look at that.

Sandy, June 2008

it happened to me on thursday it was misfiring when i was driving home from work called out AA they checked it out and was coming up as a fault four which meant coil or leads but when he stripped it down it was full of water and he had to dry it out it is coming from my washer jet

john conroy, June 2008

my ford escort misfiring

CHRIS, April 2008

Sounds to me like you have possible PCM problems (engine ecu) or a fault in the loom suppling the earth pulse to the fuel injectors.

Lee Grimble, April 2008

If it is an early 2002-2003ish MK6 then they didnt come with rubber washers under the washer jets which means water tracks through the holes into where the spark plugs are....This happened on mine. Installed later washer jets which come with a seal and that sorted mine out. You would have noticed the spark plugs and ht leads being damp when you replaced them if it was this.

Nath, April 2008