Occasionally, when I insert the ignition key into the ignition barrel, the key won’t turn (in either direction). Normally after twisting back & forth a couple of times, the key turns within the lock allowing me to start the vehicle.

Last week, after filling up with gas – the key would not turn, no matter what I did (attempt to move the shift out of Park, turn the steering wheel and depressing the brake pedal etc). I was unable to move the vehicle from the gas pump, with it being locked in Park.

Eventually, after 20 minutes (for no obvious reason) the ignition key moved freely within the ignition barrel – allowing me to start the vehicle.

Since then everything was OK, until this morning when once again the key would not turn in the ignition barrel. The problem occurs regardless of which key I use – neither of which appears particularly worn.

I have looked at the workshop manual and it would appear that the Brake Transmission Shift Interlock (B.T.S.I.) mechanism may be out of adjustment – causing the problem; and it nothing to do with the key or ignition barrel.

Has anyone else suffered this problem and can they confirm my diagnosis – any advice on how to fix it would be gratefully received.

 

Had this problem myself.....
I was able to quickly insert the key and remove it several times to get the lock cylinder to turn. Sometimes it would happen, sometimes not. Until once I got stranded....I bought a new lock cyclinder that came with a new set of keys. The manufacturer had a tutorial on-line that I could watch for installation instructions.
The problem was, the key needs to be in the "On" position in order to get the lock cylinder out of the assembly. I was forced to remove the whole locking assembly from the steering column (this required inverted torx bits). Once I removed the assembly I was able to bang the release button with a punch on the Lock cylinder so I could turn the key. The barrel came free. I was able to replace the lock cylinder and re-install the assembly quite easily. Unfortunately for me my old key was a sentry key so I had to hold the old coded key up to the ignition to get the truck to start. The rest of that story for another day.....
Also, in order to get at the tumblers....you need to be able to turn the key to the "accesory" position....

 

I had that happeen in my 01 limited and now my 04 overland, jiggle the shiit out of it tillit started..lol so far so good ..lol

 

i have a 02 grand cherokee and it started with once in a while id have to tap the key a little for it to turn..as of last night it will not turn no matter what i try...found on google to hit it with a hammer and that got it to crank but it seems as long as i leave my key in the ignition it stays working, the second i take key out, i have to hit it and jiggle it until it will turn again...how do i fix this?

 

The lock is wearing out. Get it replaced, I extended the life of mine by spraying some graphit into it. I still have to replace it though.

 

I’m still struggling on with the original keys & lock. I have to report that since my last post I have always managed to start the vehicle within a couple of minutes (at worst), and normally the key turns first time.

 

That's a common problem on those 98 up 8 cut lock cylinders Chrysler, Dodge, Jeep they're all the same. I'm a locksmith in kc and have had to service quite a few of them. very rarely does the lock cylinder need replaced. What generally happens is the tumblers build up with dirt causing the tumbler to get stuck and not pop back up this causes the sidebar to get hung up and not drop down like it should. you should see 4 tumblers in the top and 4 in the bottom. usually its the first one or second one that's stuck down.
Sometime because the key actually goes through the tumbler it will wear burs in the tumbler but that can be fixed with a small file. Just lay the tumbler flat on a small file and rub it out. The cylinder does have to be in the on position to be removed. the retainer sits right on the bottom of the lock cylinder.
Most of those stuck ignitions could probably be kinda fixed with a penetrating oil. Most people will wait to long before they do anything with it. then you play hell trying to get the cylinder out. If you don't do anything with it it will eventually get worse and leave you stranded. Time to fix it is when you see it becoming a common problem.

 

Great post...thank you.

I was thinking penetrating oil while reading this thread and saw your mention. Would it be a better idea to spray a small squirt into the cylinder with the straw attachment... or spray on the key a few times and insert/remove the key to lubricate the tumblers?

 

Yeah spray it inside with the straw. actually brake cleaner with the straw works pretty good to clean a lot of that crap out. only bad thing is it evaporates don't really lubricate. might try some brake cleaner first and follow up with like a pb blaster. be careful with the brake cleaner don't get it on any of your plastic and don't go crazy with it.

 

You might try some plastic-safe electrical cleaner.