Hey lads, still trying to resolve this cold idle issue I have with my car, it's only when it's dead cold and only rough until it drops to idle RPM's. I've replaced the entire CCV System, new Rocker Cover and gasket, MAF, both intake boots, Spark Plugs, Brand new DISA Valve yesterday, both pre cat Lambda Sensors with bosch units. Not sure where else to go, I keep getting the same two Bank 1 and 2 lean codes on Carly and the odd thermostat heating fault, I'm sure the thermo is due replacement as it doesn't always stay at 90°, but only colder. Would a faulty thermostat cause it?