Cadillac Repair: intermitent no starter engagment, seville sls, chasing ghosts

Question
2001 Seville SLS. Good running condition.110,000 miles.Good battery. I'm thinking a sensor problem?
Every week or two when I most need it, I turn the key, all sounds and looks normal except starter does not go. Get out,rock the car, take it in and out of park,it will usually go.  Worse than ever yesterday-backed up an inclined driveway,parked with back end up the hill. Next morning, about 25 degrees F. No go,rock or not. Rolled it done to level ground, it started right up. I do some work on vehicles because I am able to and I enjoy it but this Caddy,the beauty that she is, is almost too much fun for me!

Answer
Hello,

Intermittent problems are almost impossible to find. I don't think rocking the car has anything to do with the quick fix and may be coincindental to something else you are doing at the same time.

When diagnosing an intermittent problem, one is looking for some type of common denominator. Not being at the car when it is doing this makes it absolutely impossible to even guess at.

I don't want to see you chasing ghosts and changing out good parts on a guess. You are going to need more frequency, but if I were you, I might think this may be an intermitent starter problem.

Rob