mk3-ralf

Would just like to say hello, recently bought a fiesta after many years in the VAG scene.

the car ran perfectly fine and started first time, was just very low on petrol. After jacking the car on stands to give it a full service the car does not start. I have taken it off the stands now.

I initially thought it was because of petrol, but that is clearly not the problem anymore.

I called the AA out today who finally managed to get the car to idle after a push start. But misfiring on cylinders 1 & 3. After testing a new coilpack he had in the van it fired on 3 cylinders. I am slightly confused as i understand 1&4 fire off one coil and 2 & 3 off the other.

I would be grateful if anyone could give me some advice before i fork out for a new coilpack and leads. Have already fitted new bosch spark plugs but have been recommended by the AA guy to ditch them and buy NGK.

Final point, all for leads produce a good spark when outside of the cylinder.

Any ideas how this can happen just from changing the oil and coolant? I have even tried the old plugs again which made no difference.

zetec-Sam

iTrader: (2)

First, fit new ngk plugs. If it's not the plugs. Coilpacks are notorious for packing up on zetecs!

mk3-ralf

Thanks for the quick reply..i have just ordered new NGK plugs.

With the coilpacks i have seen prices ranging from £63 to £15. Has anyone had experience with the cheaper ones from ebay? Usually i would go for OEM parts and pay that little bit more but i am on a very tight budget.

http://www.ebay.co.uk/itm/FORD-FIEST...item4cf561bef4

ChrisH

How do you know it's misfiring on cylinders 1 & 3?
If all four leads have a spark and a good spark, you've fitted new plugs, it's probably a fueling issue. If you can get it running, Check the fuel pressure, if it's alright, get some noid lights (quite cheap) and check the wiring loom Injector plugs, to make sure they're all firing.

mk3-ralf

we got it running by push starting it. when idling we pulled the leads off one at a time and pulling the wires from cylinders 1 and 3 made no change. Although now its back on my drive the engine wont turn over again!

they all have a good spark out of the cylinder but cannot confirm whats going on when they are under pressure in the cylinder.

Sorry to sound so incompetent but fiestas and fuel injection are not my strong points. How exactly would i go about checking the fuel pressure?

ChrisH

Just weird that the Leads all have good spark but when plugged on, two missfire. If you took a Spark Plug out now, what colour is it? Correct electrode gap?
Does sound like a coil pack, but i'd still check everything else first.
You'd need to plumb a fuel pressure gauge into the fuel line, i know bigger cc Zetecs have a bit in the fuel line where you can just screw a gauge on, but i don't know about the 1.25 Zetecs, i presume they would.

mk3-ralf

Cylinder 3 & 4 have a orangey gunk around them and on the spark plug threads. 1 & 2 are clean. This confuses me as 2 & 4 are firing.

Spark plug gaps I have not touched because they are preset. The old spark plugs are causing the same problem which were definately firing correctly before the car went up on stands for a couple of days.

I'm assuming fuel is fine because the plugs are getting covered in carbon buildup in the cylinders that aren't firing.

I will check the resistance on the leads tonight with a voltmeter to definitely rule them out as the culprit!

Unfortunately I don't have access to a lot of these tools including the fuel pressure gauge and cylinder compression tester and I'm only have self taught knowledge of motors.

zetec-Sam

iTrader: (2)

The plugs were preset by who? I always gap new plugs!

Orange gunk may have something to do with bosch plugs, as I heard they have a tendency to leak on zetecs.

mk3-ralf

By Bosch...I would have spaced them if I could find what the recommended gap is.

The orange gunk was there when I pulled out the original NGK plugs.

tabetha

The gaps are said to be pre set, yet they fit a wide range of cars with different gaps!!, ie they're not necessarily right in your case, so gap them.
In cylinders that DON'T fire, they will just get fuel soaked, NO CARBON can build up as it needs to ignite the fuel to produce that, and they're "not firing", this tells you they ARE firing.
I would clean the plugs, and look at the lambda sensor to see if it is covered in orange stain from tesco dodgy fuel from years back, I did a car late last year a 1.25 zetec that had "passed" so called legit mot's with a duff lambda.
I would for good measure change the fuel filter if not done so as well.
tabetha

mk3-ralf

Any idea what the gap should be? Can't fund it in the Haynes manual or on the net.

Sorry should have been clearer..the plugs are firing but just cant seem to turn the engine over, apart from when it is push started.

I will check out the lambda when I get a chance tomorrow.

I have a new fuel filter but decided not to change anything else until the car is running again.

botters

iTrader: (2)

the orangey gunk is usually rusty antifreeze that has leaked from the two core plugs around the spark plugs this usually knackers both the plugs and leads so get both changed and some new core plugs fitted, just because you are getting a spark when lead disconnected doesnt neccesarily mean you are getting a strong spark
worst case scenario is you will be down on compression due to an eroded valve seat from pinking caused by oil bypassing the rings which is something that is getting more and more common in my experience with zetecs, ive done 4 this year alone

zetec-Sam

iTrader: (2)

What zetec's though? Because the 1.25's are totally different to the 1.8 and 2.0's that most people think of when you say 'zetec'.

Also, I believe the plug gap is 1.3mm.