Fiesta hesitation - a cure?

[gman76]

Hi All,

I know it has been pointed out before on this forum, but I have a '99 fiesta 1.25 zetec that has the problem of low revs hesitation. I have checked the plugs - and sure enough, the insulators have black marks down them on cylinders 2 & 4.

I have removed the plugs & inserted them into the leads & rotated them to clean up the contacts which cured the problem for a couple of months. Does anyone have any suggestions on how to fix this for a while longer?

Obviously new leads is the ultimate answer, but they are expensive! Is there something I could apply to the plug tops to aid conductivity through the core of the plug rather than down the outside?

(I know, I'm tight)!

Thanks in advance.

 

[astrab00y]

hmmmmm not really- looks like u need new leads if ur positive that it is the leads that are causing the problem

 

[gman76]

Yes, unfortunately I know it's the leads causing the problem.

What I can't get my head around, is why those lively electrons would choose the awkward route down the outside of the plug, when there is a perfectly good "made for the job" route through the core!

 

[Ron Gamma]

Obviously new leads is the ultimate answer, but they are expensive! Is there something I could apply to the plug tops to aid conductivity through the core of the plug rather than down the outside?

Your car must be running on 2 cylinders only then. If the juice is routing anyway other than through the centre conductor then it can't possibly create a spark at the tip. It needs the +ve charge to jump to the -ve earth (plug core tip to body of plug/engine block) to ignite the fuel. If the plug is shorting then the cylinder won't fire.

I suspect the hesitation is the intermittent failure to fire either cyl2, cyl4 or both.
Make sure that the little aluminium caps are securly tightened with pliers on top of the plug and give them a clean with wire wool or a brillo pad. you'd be surprised how many failures these little b*ggers are responsible for.
It that doesn't work then change the plugs.
You could try a set of leads from a breakers yard but you can't guarantee the quality.

 

[Glassman]

Just had a similar probelm with a 2000 Zetec-S Fiesta. I changed the plugs and leads which cured the problem slightly.

A few days later somebody told me to change the coil/ignition pack. I did this and it has been fine ever since. Apparently the coil packs are notorious on the Fiesta's.

A new one will cost you about £60-£70 from ford or £30-ish off ebay and it only takes five minutes to swap over as they're only fitted with 4 hex-screws.

 

[gman76]

Ron, yes the intermittant firing is the cause of the hesitation, when I cleaned them up, it drove flawlessly for a while. I guess I'll just have to clean them up again & tighten the caps.

If I get no joy from this course of action, I'll look in the coil pack's direction.

Thanks to all for your responses.

 

[johnwr]

Ford has had a big problem on zetec engines in escorts and mondeo's, the only cure is to fit new leads and new plugs. Don't just change the plug or the lead, the problem with come back to haunt you. Phone up your local ford parts department and have a word about your problem, they may be able to help. If you get no joy from them don't buy cheap leads, I think the only cure is to use Ford leads.
regards johnwr

 

[gman76]

Thanks John, although it's not really what I want to hear, as the leads alone are rumoured to be £70+ for the Motorcraft ones!

Presumably, Motorcraft ones aren't essential, they just have the tall plug caps to bring them up to the top of the cam housings? I haven't really looked at the other ends I must admit.