Dials going funny and clicking from bcem

H i all the other night i put the battery back on my p38 as when i am not useing it so as to avoid discharge . drove fro around 45 miles parked up locked up went away for around 4 hours open with the remote ok. Turn the key nowt no lights just a dull thud try it again check battery was not loose all ok lights worked radio worked just no dash light .phone up rac 1 hour wait. so there trying every now and then . Then bingo its working all lights on started. but then every so often the warnig lights come on battery fuel overheat and dials drop down with a clicking from under my seat but car drove ok any help sorry so long winded

Drop test the battery, connect a multi-meter to the +ve /-ve of the battery and then try start it, record the voltage on the meter, anything below 9.5 volts while cranking and your looking at new battery. Also look for bad earths, fuses and poor electrical connections/lose plugs.

I take it a V8???

Just had the same thing, twas the battery. Got an Alphaline D31-1000 from battery Megastore it's the biggest one that will fit in the space. 135Ah 1000CCA