I made a key for an 04 Chevrolet Impala the other night and had a call-back as a result.
When I arrived the customer had the dash off in order to replace the radio with a new CD player and had lost his only key. No codes were available so I got to do it with my A-1 tool.
The last one of these I did was the first one I attempted and discovered that I was missing the tension wire and failed at the attempt. (I hate that.) This time I had the new wires back at the shop, and had to make an additional trip to get them.
There was no code on the lock so I decoded it and cut a key. This key worked flawlessly and I went on my merry way. Last night the customer calls and reports that his key won't turn unless he wiggles the heck out of it. Yikes! this is one of those pricey MRD ignitions and I was really hoping I was not going to have to eat one of these.
I wiggled the snot out of the key got it to turn and removed the cylinder. I took it apart and promptly lost the spring and plunger. (Good thing I had a spare.) With the plug in hand every thing is working fine, the cap it tight, the side bar is dropping each time and the key is working fine.
I hate this as I knew something was causing the problem, but I could not see what it was. I reinstalled the cylinder and it does not work properly. Arrggghhhh.
I removed it disassembled it again and still no apparent cause and it is working smooth as silk. I reinstalled it and it worked fine so I snapped the plastic bezel on and hello, the problem returns. Upon close inspection, the key I used was a little short and the head of the key was hitting the bezel. I cut a key on the longer blank and solved the problem.
Something to keep in mind.