Does anybody know if brand new HT leads can be faulty. I've recently changed both the leads, plugs and extension things from the coil packs on my car. The car started to get a misfire not only at slow speeds but at high speeds as well. I've taken the car to a friend of mine who has connected it up to his computer and checked all the sensors etc. He says that all the readings are correct and when he looked at the leads and plugs they appeared to be corroded slightly on the outside of the plugs and left a brownish deposits on the leads. There was now water in the wells and he says that replacing the leads and plugs will solve the problem. Trouble is there bloody expensive and after only just replacing them don't know if it will solve the problem, but i'm not a mechanic. Anybody have any experience to comment about the condition of the leads etc.
Reluctently am going to replace them again, if its not the problem then i may have a full set of leads, extension things and plugs for sale 1.8 16v P reg. Only done about 5K.