I have a 2000 KJ Ei which has Cruise and Traction Control systems.

Began to give trouble yesterday morning - a long way away from home of course.
Same symptoms happened this morning.

When first starting the car from cold - sitting overnight at motel - the car started immediately with the brief flare of Revs and then idles like normal. BUT, idle is ALL it will do - no response from Accelerator Pedal (which may or may not feel a bit "dead").

Yesterday we were out of the motel carpark and idling along a side street before we noticed this problem. We fiddled a bit in the cabin, thinking it was a mat caught under the pedal etc. Eventually a "stop the car/re-start the car" gave immediate return to normal. We were not sure if the "TCL Off" light was flashing or not yesterday - thought we might have bumped the TCL button near the Ign Key.

Today, we noticed the same issue while still in motel carpark and pulled up in spare spot.
Definitely nothing wrong with pedal in cabin. Popped bonnet and pulled on Accelerator cable near the Throttle Body - no response, car simply idles. No stalling with "throttle-on" or "throttle-off".

Tried turning AirCon Off and On a few times (thinking of Air Con Idle-Up etc) no difference. Restarted car a few times, no difference for a while. "TCL Off" definitely flashing this time. Switched the "TCL" near Ign Key a few times, no difference.

Read the glovebox manual a bit - no real information. Eventually as car warmed up we could hear Idle Speed dropping back and after a few minutes we had normal Accelerator response, and stayed that way all day (covered about 300kms with lots of stopping and re-starting in different towns on the way).

Haven't spotted too much directly relevant in the "online PDF Workshop manual".

Thinking perhaps "Accelerator Position Sensor" (TCL cars only) or "Throttle Position Sensor" might be involved - will try to test tomorrow morning if problem occurs again when dead cold.

PS: Been out of Forums for a couple of years. 30 yr old "new" house to play with, maintain etc. have hardly even lurked in Forums due to time constraints. Both my KJ and TJ Sports got hammered in hail storm about 2 wks back. KJ was Written-Off immediately and I have bought back for $600-00 - it is logged with NSW RMS as "superficial hail damage only" so Rego continues etc. For the TJ, I am still waiting to hear from Insurers, may be fixed or may be write-off also. Now shopping for carport!

Update: Car had exact same symptoms this morning: Starts first go, revs flare briefly on start-up (just like normal) , then settle back to fast idle. using Accelerator makes no difference to idle speed, no revving.

As the car warms up, idle-speed drops back. Using Accelerator pedal has no effect. Temp guage comes up to normal heat range and idle drops to normal idle -stable idle speed etc. After a while longer, can accelerate as normal.
Seems like "TCL OFF" light does not illuminate until car is in-gear or moved.

Think I will drive it another 200kms or so today, to get home - and get a local garage to try to read a Fault Code. Wishing I wasn't about 1200km from Mits-Fix, LOL!

Clean your TB, is the throttle plate sticking in gunk in the TB, as you have TCL the plate is not directly connected to the throttle cable, it is connected via a spring

Thanks Mal - I had briefly considered the butterfly getting stuck in gunk. Will give that a go and let you know. Beast is about due for transmission service from a family-run business I trust - might get them to have a bash for me (trying to paint storey-and-a-half balcony railings in amongst bloody rainstorms!).

Well, all afternoon painting bloody balcony railings (at least the undercoat is complete), I was freaking-out thinking what the apprentices at one of the auto-trans places might do to my Throttle Body when I leave the car there tomorrow for a per-20K transmission service and leave it a few days before I collect the car. (I had asked them to also clean throttle-body when I booked the Trans Service).

Painting completed, with a bit of light left, I have attacked the throttle body in "5 minute" mode - pulled air cleaner element and airflow meter out, attacked throttle body from air-inlet side only. It wasn't really disgusting, but managed to get a fair bit of gunk off the lower side of opening, and off the edge of the butterfly. I feel a lot more confident now to let the local boys look after the transmission and I will tell them to leave the Throttle Body alone. (I had nightmare visions of them unscrewing Throttle Position Sensor and Accelerator Position Sensor off the Throttle-Body, with no idea how to set them).

I'm sure a proper clean by removing throttle-body will do better again than my quick "in the half light" effort, but hopefully what I have done will make a difference. My poor old 'Rada' is still a magnificent beast in my eyes, despite a hail storm making her now a "Statutory Write Off". A year or two out of garaging means she now has sagging of headlining and even on the door cards. If I ever get the house chores sorted, the 'Rada - now in "golf-ball-finish" - deserves a bit more care and attention! Thanks Mal for your advice - really appreciated, as always.