Have to shake steering wheel to start the vette where do I start to fix.

75 Chevrolet Corvette Stingray

84 Honda V65 Magna 

86 Honda Goldwing 1200

2000 Ford F250 Super Duty 

2015 Kenworth T680 

All I can think of would be to start w/ the ignition switch.  It's at the base of the steering column and is connected by a rod to the key lock.

1973 L-82 4 spd

That's where I would start to look too.

At about half-way down the steering column is a long box-like thing where wire ribbons connect to; one ribbon from the steering wheel and one going under the dash, held on with a couple screws IIRC. It is a slide switch, which is activated by a rod that comes from the Ignition Key mechanism. Shaking the Steering Wheel may have something to do with that Rod moving slightly enough to allow the switch down there to make contact. It's contacts could just be dirty/faulty.

I'd check out the security of that Rod and lower Switch first. Ignition Key Switch mechanism, to see if it's pushing the Rod down far enough to activate the lower slide Switch, would be my 2nd choice to look.

Good Luck.

Steve

Just as a F.Y.I. There is a slight amount of extra slot in the switch. It can be adjusted on the column at the screws a tad to make better connection, or engaging in the contacts. 

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