Hi all ive got a discovery 3 2.7 on a 2008 plate i keep getting a fault code of p023d-21 so i smoke tested it as its down to an air intake problem had no smoke coming from anywhere on the outside of the engine so i thort that was odd and then i took the oil filler cap off en the smoke from the smoke tested was comeing out off the rocker cover and also pulled out the oil dipstick and was coming from there aswell could the rocker cover b cracked or split on the inside? Any1 with any info on this wood b fantastic thanks for ur time
