Fiesta Misfire - coil, leads...or worse?!

Fiesta Misfire - coil, leads...or worse?!

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KatieDee

Original Poster:

8 posts

126 months

Wednesday 21st May 2014
quotequote all
Sorry in advance for the essay guys!

My 53 plate 1.4l zetec fiesta began juddering a few weeks ago. I called the AA who checked and changed the spark plugs, sorted my leads, put a litre of oil in and did a quick check on the misfire (all seemed fine). They advised me to drive home, car still juddering but not as badly.

I took it out the day after and the juddering (especially in low gears) was much worse, plus the engine light was flashing. I carefully drove it home, did some Googling, ended up changing the coil pack and replacing the leads. Problem still remains.

I had a mobile mechanics visit yesterday who carried out a diagnostics test and found the 2nd cylinder was misfiring. This is a brand new coil pack so I'm assuming this shouldn't be happening. The coil pack was from Europarts and the numbers for the leads are the opposite from the original Motorcraft one (actually proving impossible as the leads aren't long enough, which the mechanics confirmed) which I thought might be causing issues...but there's no other way to connect, plus it doesn't explain the oil...

I checked the oil and there was hardly any in. I'd driven literally 8 miles since I'd put a litre in. Mechanic suggested it's more than likely a piston issue, given the rough idling, the smell of fuel when revving and the excessive use of oil.

61,000 miles on the clock and a knackered piston on a Zetec doesn't seem right, so thought I'd ask for a second opinion. I'm a day away from selling it as scrap, as the wheels need fixing and brake pads replacing, plus I'm coming up to a cambelt change.

Can't get it to a garage due to it holding no oil. Main symptoms are

Excessive oil use
Smell of fuel when engine running
Juddering in neutral
Over revving
Engine light flashing after driving more than 50m
Low rumbling from exhaust when revving (similar to blowing)

Any advice appreciated :-)

LuS1fer

41,715 posts

252 months

Thursday 22nd May 2014
quotequote all
Get the codes read.

One very common issue with the Fiesta is the throttle position sensor in the throttle body. It will ordinarily throw a message about the engine on the dash.

Though the earlier models seem to have a cheap, easily replacable TPS, the later models have "fly by wire" (electrical connection) throttles and seem to require the whole throttle body/integral TPS replacing.
Ford want £400 for a new one but ebay do them for about £260 which is why you need to get the codes read FIRST.

You can buy cheap code readers off ebay - OBD code readers - for £15 or less.

Grab the code then google the result for the symptoms.

One post suggested checking the connector to the throttle body which can sometimes get water in it or removing and cleaning the throttle body with spray carb cleaner can sometimes help.


Edited by LuS1fer on Thursday 22 May 08:41

TheFinners

544 posts

134 months

Wednesday 4th June 2014
quotequote all
Had a similar problem on mine, although it was mostly just misfiring under load at <2000rpm and also the 'blowy' exhaust sound. Eventually found that rainwater was getting into the spark plug wells via the washer jets. To sort it we used some bathroom seal round each washer jet (Ford actually bothered to seal them on the facelifted models) and got the water cleared out and spark plugs changed, and it has been fine ever since. The garage also pointed out that my car had been fitted with a non-genuine coil pack so if the problem returned it would probably have to be changed for a genuine Ford part.

robminiman

230 posts

192 months

Wednesday 4th June 2014
quotequote all
first things first, do a compression test. when doing a compression test all cylinders within 10-15% of each other. i did a 2000 1.25 fiesta about 5 years ago were it had a broken piston ring on one of the middle to cylinders so had much the same symptoms as yours.

Rob

neiljohnson

11,298 posts

214 months

Thursday 5th June 2014
quotequote all
Could be a faulty part although that wouldn't explain the oil use but that amount of oil would either mean a very big puddle under the car or clouds of smoke out the back
I've seen problems with bosch branded spark plugs recently so worth checking that

If the car really has an internal issue then a simple compression test will tell you all you need to know & this would one of the first checks any mechanic worth his while would have done when diagnosing the running fault.

chrisa6

2 posts

117 months

Sunday 5th March 2017
quotequote all
Neil, your comment about Bosch plugs is interesting. I've recently bought a 2004 Fiesta 1.4 for my son to learn to drive. I've given it a "full" service including new (Bosch) plugs and fuel filter.
The car is juddering (misfiring) at around 2000 revs under load.
I thought new HT leads may be required but would appreciate thoughts on this.
Thanks
Chris

chrisa6

2 posts

117 months

Monday 6th March 2017
quotequote all
Neil, your comment about Bosch plugs is interesting. I've recently bought a 2004 Fiesta 1.4 for my son to learn to drive. I've given it a "full" service including new (Bosch) plugs and fuel filter.
The car is juddering (misfiring) at around 2000 revs under load.
I thought new HT leads may be required but would appreciate thoughts on this.
Thanks
Chris

njw1

2,237 posts

118 months

Monday 6th March 2017
quotequote all
If it's missing and/or juddering the first thing I would check is that there is no water getting into the spark plugs wells as mentioned above, if there is or was I would suspect the coil pack is at fault as these seem to be very sensitive to blowing if the spark plugs have been immersed. I wouldn't recommend driving it either until the fault is resolved as on my missus old Fiesta I ended up with two dead coil packs and a dead ecu before I found out about the leaky washer jet problem.

cncsteve

1 posts

147 months

Sunday 24th September 2017
quotequote all
i know this is an old post but had a similar problem with my daughters Ford Fiesta 1.4 Zetec
i sorted it out by 1st changing the windscreen washer jets that were leaking and when it rained was allowing the water to run down into the engine bay and find its way to cylinder No 4 causing corrosion to the spark plug
Changed the spark plugs but set the gap to 1MM not 1.3MM
now the car run like new