Hiya, I Have A Ford KA & Its Running On 3 Cylnders And The Engine Management Light IS ON We Can't Seen To Fine The Problem. We Have Put New Spark Plugs & HT Leads And The Problem Went Away For About 10 Mins. Can Any 1 Tell Me Whats Wrong With It.

 

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how old is the ka and what engine

 

a diagnostic place should be able to read the fault code and tell you on which cylinder the problem is. i had this problem on a ka, and i was able to cure it by regapping the plug. the wasted spark system tends to eat through plug centres quite quickly.

 

it sounds like the coil pack is breaking up, if you pull the plug leads one by one you should notice the engine running worse on 3 of the cylinders and just the same on the bad one or the bad pair, then fit one of your old plugs to the bad cylinder/s lead and earth it (by touching the engine with the metal body of the plug) and check for a spark no spark bad coil or engine management fault (very unlikely), use well insulated pliers and/or thick work gloves when working on the ht side of the ignition circuit it will give you quite a shock , you could also check the condition of the wires feeding the coil i have seen a couple that have broken one and only run on 2 cylinders