Ford Focus Saloon 1800 petrol - 1800 focus no spark on one coil pack lead

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Thu 13 Apr 2017 11:56
Ford Focus Saloon 1800 petrol - 1800 focus no spark on one coil pack lead - ROBERT langley

Car is stalling once warmed . Orange cog exclamation light comes on and car loses power. I've pulled the coil pack leads and 3 are sparking but one is not. Any ideas guys ? Thanks very much in advance.

Rob

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Thu 13 Apr 2017 14:06
Ford Focus Saloon 1800 petrol - 1800 focus no spark on one coil pack lead - Railroad.

Faulty coil pack. Very common on these.

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Thu 13 Apr 2017 14:17
Ford Focus Saloon 1800 petrol - 1800 focus no spark on one coil pack lead - ROBERT langley

Even with the lack of spark on the 'distributor end' I know it's not a distributor but where the leads push on on the opposite end from the coil pack.

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Thu 13 Apr 2017 16:44
Ford Focus Saloon 1800 petrol - 1800 focus no spark on one coil pack lead - ROBERT langley

Put a new coil pack on it and still cutting out badly. Car sounds as if it's choking and then dies. Restarts and drives for a few mins and dies again.

Any ideas guys ?

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Thu 13 Apr 2017 17:20
Ford Focus Saloon 1800 petrol - 1800 focus no spark on one coil pack lead - elekie&a/c doctor
Are you sure it is not firing on 2 cylinders?
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Thu 13 Apr 2017 23:43
Ford Focus Saloon 1800 petrol - 1800 focus no spark on one coil pack lead - Railroad.

Blocked catalyst perhaps, resulting from an on-going misfire?

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Fri 14 Apr 2017 13:19
Ford Focus Saloon 1800 petrol - 1800 focus no spark on one coil pack lead - Cyd

Highly likely to be the coil pack, but it could also be a HT lead. Follow my method in this video to test the pack and leads, but you'll have to 1/ earth the plugs with a suitable wire (jump lead is good) 2/ swap the plug and lead from a good cyclinder to check if it's coil or lead (or even plug) 3/ buy a Laser spark tester from your local factors if the makeshift tool gap still shows a spark (or make one using some wood and wood screws). A misfire can damage a plug too, so if there is any doubt replace them.

If you've got a code reader app then the code will tell you which cylinder is misfiring, but you still need to test because it won't tell you which part is faulty.

https://www.youtube.com/watch?v=BeJ0P9XTBRg

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Fri 14 Apr 2017 18:01
Ford Focus Saloon 1800 petrol - 1800 focus no spark on one coil pack lead - skidpan

Simple fact is with wasted spark and a double ended coil you cannot get misfire on one cylinder. The electrical pulse goes down one lead across the plug, through the head back through its paired plug and then back to the coil. On later genuine Ford Platinum tipped plugs to save money the Platinum is on the centre electrode on one plug and on the "earth" electrode on its opposite. When I first got a set I thought I had been sold a pup but it soon became clear what they had done.

Did you buy a genuine coil pack or a cheap copy?

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Fri 14 Apr 2017 18:29
Ford Focus Saloon 1800 petrol - 1800 focus no spark on one coil pack lead - Railroad.

Simple fact is with wasted spark and a double ended coil you cannot get misfire on one cylinder.

Correct in theory, but not in practice. It's not uncommon for wasted spark systems to misfire on one cylinder. It depends what is wrong with the coil. The secondary windings could be open or short circuit, and a high voltage could still be induced on one side, and track to earth on the other, which means one cylinder of the pair will still fire.

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Fri 14 Apr 2017 20:44
Ford Focus Saloon 1800 petrol - 1800 focus no spark on one coil pack lead - bathtub tom

On later genuine Ford Platinum tipped plugs to save money the Platinum is on the centre electrode on one plug and on the "earth" electrode on its opposite. When I first got a set I thought I had been sold a pup but it soon became clear what they had done.

How do you know which plug you fit in what hole?

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Sat 15 Apr 2017 18:39
Ford Focus Saloon 1800 petrol - 1800 focus no spark on one coil pack lead - skidpan

How do you know which plug you fit in what hole?

The platinum tip is just visible but the plugs are visibly different. The spark jumps from centre to earth on 2 plugs and earth to centre on 2 plugs. The platinum goes where the spark jumps from.i.e cylinders 1 and 4 for the centre electrode and 2 and 3 for the earth electrode.

All non Motorcraft plugs I have seen are double Platinum and go anywhere.

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