Hi everyone, I'm new to the site, I purchased this GTS Panther around about 8 weeks ago, it was fine for the first 2 weeks, and then I noticed when I was going steady in 4th Gear it would start to miss a bit it's got a lot worse and now wont even tick over on idle, it looks like it is running very rich, I took out the spark plugs and they were black and the sooty I've changed the lambda sensor and air temperature sensor and the water temperature sensor and put new spark plugs in, this has still not cured the problem it's a 1.8 Zetec engine with electronic ignition omex 600 ECU it was built by Eddie99 on here, any help would be much appreciated thank you

Have you checked the fuel pressure?

No I haven't, I bought a new fuel pump as the old one was noisy, went to fit it yesterday and it had a leak, so will have to order a new one