mini going over a cliff....

[jonnocooper]

i really need some advice guys....

my 95 cooper refuses to start (most of the time.... )
it starts when i jump start it off another battery, it could be fine for a few days and then it wont start again. when i try and start it , it just makes a small noise like its going to start..... and then nothing.

i have a new battery, thats not the problem. it reads over 12 volts all the time.

the alternator is working, its been tested.....

the starter was checked out, thought that was the problem, had a new one fitted.... still wont start consistently.

just now i went out and tried it again, and i couldnt turn the immobiliser off..... would that be the problem.

at the moment im thinking about pushing it off a cliff....

any advice is greatly appreciated!
Jon

[The Marcos Graveyard]

Check your earths, you may need to clean up the points where they contact the body in the boot and on the bulkhead and block.

[woody]

Are you sure the battery is fully charged.A nearly discharged batttery will power a voltmeter but will not start the car.Likewise a bad earth connection or bad battery connection will do the same. If the car starts first time on a jump it sounds like bad batttery connections or something discharging the battery.

[Mark]

As stated, sounds like an earthing problem.

[jonnocooper]

thanks guys.... it seems to be ok the last two days..... but im sure it'll happen again.

how do i check the earthing is good?

[The Marcos Graveyard]

Check that there is good metal to metal contact between the battery earth strap and the boot floor, unbolt the strap and clean the mating surfaces with a wire brush/sandpaper, clean the threads on the bolt too,( a bench grinder with a wire wheel attachment is a godsend here (suitable eye protection is a must)).

Also check the state of the earth strap at the engine, usually mounted along with the top engine steady bar from the bulkhead, just under the master cylinders, to the side of the engine block. Rust and crud can build up here, especially the bulkhead end, again clean as needed. Be careful though, the bolt here is prone to seizure, so check first and use the proper sized socket, you don't want to gunther the head of the bolt, apply a suitable penetrating oil as needed. You could always use this opportunity to replace the engine steady bushes if they are worn. :)