Shake car to start???

This isn't my car it is my grandma's car (97 Pontiac Grand Am 6cyl) and I have no idea whats going on.

She has to rock the car back and forth to get it started sometimes as if something isn't clicking back into place.

There is no codes and when it does start it runs smooth and still feels like its fresh off the lot. I mean its a smooth ride.

It doesn't do it at any perticular time, it just happens hot or cold.

She took it to a mechanic twice, both said it was fixed but it still happens.

WTF could it be?

I dont want my grandma calling me one night saying shes stuck somewhere and her car wont start.

This sounds like a loose connection probably a ground wire. It could be the main ground or the ground for the ECM. Check all connections to make sure they are tight and look for corrosion under the ignition module it may not be making good contact.

As simple as that?

So either the shops she took her car to are imcompetent or they are trying to hussle my lil old grandma.

Some shops are good at taking little old granny's for mega bucks since they don't know what is really going on and are quite trusting.

(Just as an example, I once had an ambulance that refused to charge. Everytime I worked with the relay it worked for a few minutes and it stopped. Turned out the plate the charging relay was mounted on was corroded and would not let the ground make contact so that the relay would work. Simple to fix but a hassle to find. Ran a ground direct to the battery and never had another problem.)

loose wire at the starter.

looked like it was in all the way but when I tester it with my little wire power tester (i just forgot what its called) it showed power, shook the car and went back to it to check again and it barely showed any power.

pushed on the wire and it went in snugly.
i took it off and cleaned it just in case.

I think they just wanted to take my grandma's money.
and she told me one of them wants her to come back so he can do another check to make sure the fix took hold.

WTF?
To see if the fix took hold?
Total BS.
I bet he knew what was wrong and wanted her to come back and say it wasnt fixed so he could come with something like "O The (insert big expensive sounding car part here) is also broken its gonna cost (insert big ass number here) plus tax and labor.
Then all he would have to do is plug in that damn wire.

Well now that that is off my chest.

THANKS GTP DAD
You saved my grandma mucho $$$$.