After reading many links here and the DieselGiant pictoral, then talking to a buddy who is a AAA locksmith, I was able to fix his ingnition in about an hour.

The key absolutely would not turn. Wasn't sure if it was the lock tumbler or the entire assembly at fault.

After looking at all required to remove/replace the ingition lock assembly, I was praying for a simple tumbler replacement.

Anyway, after trying everything I'd read about and still not being able to get that key to turn, I called my locksmith friend. He suggested I flush, flush, flush the key slot with brake cleaner, contact cleaner or WD-40 until it runs clear (This to remove all the impacted grahite and other crud). Then tap on the bottom of the assembly whilst attempting to turn the key.

He said it was essential to tap directly parallel to the the key slot. After we flushed all the crud out of the tumbler, I crawled up under the dash and tapped with a large screwdriver and hammer while the car owner turned the key. Almost immediately the key turned.

After a few hoots and hollers, I then followed the Dieselgiant instructions for removing/replacing the tumbler. Now his key turns quickly and easily everytime.

I'd say replace the tumbler while you can still turn that key. As long as you are able to get it in the first position, you can easily get it out.

edit: If you can still turn the key, all you have to remove is the black plastic cover around the tumbler on the dash face. If the key is stuck, you'll need to take off the panels below the dash face to get to the assembly to tap on it. If the entire assembly needs to be replaced, well then you get to pull off all kinds of fun and exciting bits!

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1998 E300 +310,000K
1996 E300 +460,000K