My 1983 300D, 275K miles, has a ignition switch that needs jiggling to turn. Today, it was below 20 deg. F, and no amount of jiggling would get it to turn. So i heated the keyhole with a hair dryer, and finally it turned & started.

I see from other posts it may be a worn piece on the steering lock. When i turned it off to go into a store, i turned the key not quite all the way to the leftmost click, and it turned smoothly and started.

So i am pretty sure this means the problem is with the steering lock not disengaging due to a worn part.

I have to leave the key in to use this workaround. Fortunately i am in a rural area. Unless anyone has an idea for an easy fix, (maybe lubrication?)i will fix in the Spring by dismantling that steering lock piece.

There is no easy fix to an ignition which is hard to turn unless the problem is the ignition cylinder so here's what I'd do first.

I'd buy a replacement cylinder which has two keys and replace that cylinder so I could lock the doors while leaving a key in the cylinder in the unlock position.

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84 300SD
85 380SE
83 528e
95 318ic

If as i suspect, it is the steering lock mechanism, i don't think a new cylinder would help. The door locks also don't work, but i think i would get a spare key made before changing that cylinder.

Ignition key intermittently hard to turn.

Well, it could be the lock tumbler or the inside of the steering collum lock.

When I was faced with that while the key still turned, and I could line up the parts to get the paperclip in to remove the lock cylinder I did that and inspected the lock cylinder.

With the lock cylinder out, you can give it thought cleaning and inspection. There is more than one threaded on removing the lock cylinder. If you don't find anything wrong with the lock cylinder there is a good chance it is the steering collum lock mechanism itself.

When I inspected my lock cylinder, I found it OK and decided to take the steering collum lock off and I found broken parts in that.

I don't know if new steering collum locks are even available anymore.

In the pics in the thread below is what I found. After installing the new steering collum lock 1+year later my lock tumbler fell apart.
Steering Colum Lock (Ignition Lock Housing) causes Ignition Switch Failure

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84 300D, 82 Volvo 244Gl Diesel

my solution... (destructive)

W123 key switch sticking / stuck

This was my little research project into why the column lock jammed in two of my cars. Perhaps it’ll help. It worked for me. I would not say it was easy.

Jammed ignition lock - steering column mechanism worn

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79 300TD “Old Smokey” AKA “The Mistake” (SOLD)
82 240D stick shift 335k miles (SOLD)
82 300SD 300k miles
85 300D Turbodiesel 170k miles
97 C280 147k miles

When the weather breaks, i will try to disable that steering lock.

If it jams permanently it is a major job, do your best to not delay the repair. In the interim consider removing the lock cylinder and operating it with a screw driver. It can be the lock cylinder, the steering lock or the ignition switch causing the problem.

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"Rudeness is a weak man's imitation of strength" - Eric Hoffer