The saph has been parked up for 18 months and has now gone to the garage to get it back on the road All the fluida and filters have been changed and from cold ot starts and funs perfect BUT when it gets hot number 2 and 3 cylinders drop out, the garage has done a compression test and when the engine is cold all cylinders are as they should be but when hot number 2 and 3 are done to 20 psi. does anyone have any ideas for me to pass on