Right guys here is the problem
car starts fine first time every time
Engine managment light is on
Car appears to be missfireing but it isnt
Had new coil packs
New leads and plugs
New engine coolant temp sensor (old 1 was reading 500 degrees)
Getting clear and loud signal from the ecu to the coil packs
Engine timing is spot on
300 or so mile ago engine rebuilt involing 16 new valves head check, new HG
Commprsssion test has been done and found to be good


upon having the codes read lambda sensor and knock sensor also came up.
Could all my trouble be the knock sensor as i have voltage checked my lambda and its sitting at .025 volts with slight variance
The spark Plugs are very black on then ends so i suspect the fuel mixture isnt right, but what would throw it out?

So what do you think?
Knock Sensor or may be a different sensor? ECU ECU stands for Engine Control Unit and is the "brain" of most modern cars.

bump

okay guys any ideas lol it's doing my nut in now

I have been told there is no knock sensor is this correct?

As the OP says, the rough running and black plugs suggest its running rich.

The default fuel mixture is rich for starting then when the engine heats up the lambda is switched in and the ECU adjusts the mixture accordingly.

The lambda can be damaged if much coolant gets down the exhaust system from the blown head gasket. Then the ECU wont adjust the mixture so it runs rich.