Spark plugs causing a problem

[Baz]

Car started to jerk a few months back, took it into a garage and he said it was a faulty spark plug. A new set was put in. The problem reocurred again after a few weeks, so I decided to get them changed again. All was fine until last week when the problem reappeared.

I changed the engine oil aswell as the oil filter to see if it was anything got to do with that. This kinda made the problem worse whilst driving I could smell petrol when the heater was on.

I had a look at the plugs and they were charred black ! Now i'm thinking if its something got to do with the actual brand of plugs (standard NGK) themselves or is it a problem with the spark plug leads which might need replacing ?? Does anyone know about this problem ?

Thanks in advance
Baz

 

[Richard]

Sound like overfuelling to me not the plugs i would get a diagnostic done first i will find the fault and save spending on this that and tother.

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[Baz]

Can't be overfuelling, the tank is less than half full !

 

[Richard]

Overfuelling (over rich mixture plugs turn blackish)feels choked i could be wrong though ...thats why i said get a diagnostic done !!
p.s. i hope you were joking about the half a tank bit.

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