D2 starting issues

[ubuntu]

Sometimes my D2 will not start - when the key is in the crank position the starter motor does not run and there is no click from the starter solenoid. Battery voltage is at 11.8V, but even jumping with my Jeep produces nothing. Battery is new 850CCA and I replaced the battery earth cable with a new fatter cable. The engine earth strap is good, checked that. I started reading through the electrical section of rave but that confused me more, yeah sorry I'm not following that shit.
Once it started after I swapped around the headlamp washer and starter relays and thought the relay was the problem, but no joy today.
Other stuff that happened was the engine would idle badly or cut out at a stop, but start right up again. I replaced the crank position sensor and the front O2 sensors (had a 0134 error).
And then just to fuck with me it will start perfectly for the next 10 tries :banghead:

Where do I start troubleshooting?

 

[rovercanus]

I'd say your starter is bad.

 

[ubuntu]

OK, so after leaving it for an hour and then packing away my shit and slamming the hood the fucking thing started, no kidding.

I will go dig out a starter motor at the pull a part and see what happens.

 

[Devildog01]

I think jumping it with your jeep poisoned it.

 

[ubuntu]

I took the D2 to an auto electrician and they checked out the starter and alternator (while it was there), both checked out in good shape. The ignition switch is faulty and that is the problem. I have bypassed the ignition switch by running a wire from the solenoid to the battery box, when I need to start it I pop the hood and touch the wire to the + battery terminal and it starts right away. I'm going to wire a push start button in the dash - like my new cars have