My 2001 malibu sometimes won't start for several minutes and shuts off while driving and I lose power steering. I've had the ignition replace. Mechanic put on computer and they could not find a problem.

The engine runs the power steering pump. When the engine dies, you lose power steering ASSIST. You do NOT lose steering! It does NOT lock. It's just harder to steer. There is no way for us to guess what's causing your engine to die with the scarce information you provided. Get it to a shop to have it checked out.

You are right that it could be either component, or something else electrical. The security system will kill the fuel system if the wrong key is used or the system is acting up.
A mechanic would check base fuel pressure with a gauge and also see if the pump is getting power from the relay when it fails to start.

Sounds like you may have a wire heating up and grounding out or a wire loosing contact.

Hi, The clicking you hear is the anti theft system has been triggered, beneath the steering column pull down the fuse cover and locate the (ECU) fuse Labeled so on cover and owners manual. Remove (ECU) fuse turn ignition to on only, do not start, wait 3 minutes turn off ignition remove key, reinstall (ECU) fuse. Try starting Vehicle!

Hi with an old vehicle like yours, first thing which comes to my mind is the ignition switch and or a loose ground some where close to the battery.

OK, obvious first: turn it the other way. Don't laugh, I've done this.

Otherwise, barrel is jammed. Get a new barrel, dismantle the steering column and replace the existing one. You'll now need two keys: one to unlock the car and one for the ignition. You won't be the first.

Sometimes the steering wheel has a lock mode when the car is off, and then gets stuck there. Try wiggling the wheel after you start the car.

The ignition lock cylinder tumblers get in a bind all the time on GM vehicles. It probably has little to do with inseting the wrong key. Try inserting the correct key and "jiggle" the key in the lock. You may have to jiggle it up and down and rotate (or try to rotate) the lock cylinder forward and backward. It will probably work just fine if you can wiggle it with just the right combination. If not, you may have a damaged lock cylinder and you will have to replace it. - most likely nothing you did....I change at least two or three of these things every week...VERY COMMON.

Sounds like a bad connection to the starter somewhere. I'd start by checking that the wiring connections to the starter are clean and tight.

its the problem with your ignition coil . Replace it and check for loose connection towards the ignition coil connector kit