GMC ENGINE NOT CRANKING OVER

I Have A 1998 Gmc Sierra Extended Cab 1500. It Has A 305 V8. I Had Just Poured In A Fuel Additive (sea Foam)and Filled Up With Fuel Gas...

I Turn It Over And Sometimes It Will Not Get Electrical Connection.

I Have A 1999 Gmc Jimmy And It Stops And Wont Turn Back On After 30 Or 60 Minutes Of Driving, It Cranks But Wont Turn On But If I Wait 30...

The Car Does Not Crank, The Anti-theft Light And The Parking Brake Light Stay On Solid Even When Key Is Removed, And Doors Are Shut And...

It Just Goes Click Once And That's It.

Had Injector Replacement And Distributor And Fuel Filter Ran Good For Little While.

My Anti-theft System Is On And No Communication With Ecm And Not Telling Me What Gear I'm In And Saying That Trans Is Hot, And It Won&#...

While Cranking Engine Makes A Loud Clank Sound.

Replaced The Steering Column And Key Now The Security Light Is On And Can't Get The Truck To Turn Over. I Checked All Fuses And Battery...

When Cold Outside Under 45 Degrees No Crank No Start. But When Over 60 Degrees Starts Fine. Also, When Over 45 Degrees Car In Limp Mode But...