I am new to land rover , and have purchased very cheap a 96 disco 1.
I knew there would be a few problems along with it since it has 135000+ on it. I replaced the y cats,the plugs and plug wires,power steering hoses, cleaned the maf and sensors. It sounds great at idle when cold and hot but when I take it on the road and accelerate hard It makes a hissing sound you can hear inside theLR. It sounds as if it's coming from the lower part of the engine up front. Could this only be a manifold gasket or cracked manifold or an even bigger surprise?

 

Please post your question in the Disco area to get some help.
Mike