Is your EF or EL Falcon loosing a lot coolant but there is no evidence of a leak? Now I’m not trying to scare you, but it could be that the head gasket is leaking, albeit in a place that hides the evidence very well! We have seen this issue many times over the years so I thought it would be wise to document the next Falcon that came in with the problem.
The area I am talking about is behind the exhaust manifold and can only be seen by removing the heat shield – two 10mm bolts down the bottom and two 13mm manifold to cylinder head bolts.
Have a look in the area around the fourth, fifth and sixth cylinder for evidence of scum buildup between the block and cylinder head and down the surface of the block –
Obviously coolant loss can be caused by many other things, but if you are having trouble identifying the source it may be worth your while removing the heat shield and taking a beau peep.