I have a 2005 r53 auto that I have replaced starter twice, ignition switch, and cleaned engine ground connection and still intermittent start. When key is turned lights and instrument cluster function normally. Any ideas what to check next?

 

spark plugs, wires, coil pack, and battery would be good to check.

 

battery and ground issues tend to result in the cluster, radio, everything on when the key is in the ACC position to work fine, BUT usually when you try and start the car, you will turn the key, may hear a whirring sound, and the gauge cluster will flicker and you should hear a clicking.

usually for me the dash and gauge cluster will stayed dimmed for a few seconds, then come back.

If this happens I start looking for grounds or battery terminals.

If you can put the car in gear and rock it back and forth some and then hit the ignition and it works, it is most likely a contact or a brush in the starter motor and it needs to be replaced.

(old school method of determining if it is the starter)

If it does start, do you have any issues keeping it running?

normally cold starts?
hot starts?
mixed/ random?

worse on cold mornings?

etc etc.

 

After started car runs fine. Starting issue is random (sometimes when hot and sometime when cold) I can't seem to narrow down a pattern. I first thought that solenoid was getting hot and I put foil insulation sheet on heat shield over starter, still intermittent with new starter installed. After starter was installed was good for couple weeks then started having problem again. I'll will check ground connections and battery terminals.Thanks.