my 512TR won't accelerate til temp is up...

Well first off, no it's not normal 512TR behaviour. At least I've never had a moody car that went to sleep just because it was cold (and I live in cold, rainy Europe). It's probably one of those cheap tiny faults that is holding you back. Firstly, let's assume you're pressing the accelerator and not the brake.

As a guess, it doesn't sound like engine, transmission or big stuff since you don't describe smoke, or weird noises. So it's got to be fuel, air, or electronics (sensor/controller) probably. One thought that comes to mind is if it's only running on 6 cylinders but then you don't mention getting any dashboard lights coming on.

Next, I presume the fuel is good and that you haven't left it sitting for years to varnish the inside of all the lines and other parts. You could always shake the fuel filters or replace them if they're due anyway. Also check air filters/boxes for blockage (mice perhaps!) All very unlikely but worth a shot.

A basic check is to switch off the car and have a buddy look into the top area of the engine (behind the coolant reservoir) and see if there is movement as you press the accelerator pedal. Hey, no harm checking.

What about the clutch - you're not noticing any 'fishy' smell as it tuns to toast near its end-of-life. No, I guess not.

So you've probably got a sensor fault, or perhaps just a dodgy connector. With battery disconnected, I'd try disconnecting connectors around the engine bay (and relays in the front) and then reconnecting them again. Look for obvious connector corrosion while you're at it. It doesn't do any harm to wiggle the spark plug wires either, but again faults there would cause enough hassle for the slow-down light to come on.

If there's still no sign and you're unsure about going further then I'd just take it to the dealer and ask for their diagnosis - they can check quickly and if you stick around the bill for time should be modest. Hey, at least you can drive (slowly) away if you're not happy at the state of progress.

Sorry I can't help more, but with so little infromation to go on it's hard to say - anyone else had this fault out there? And no jokes, about going up hills in the cold, or potatos in the exhausts.

 

Check your throttle linkage, it could be sticking. Next see if the intake butterfly isn't sticking.
If all mechanical devices are free then move up to sensors such as your temp sensor on the block.
A deeper scan could involve checking the fuel pressure while the car is cold.
Another side of this multifaceted coin is to check your ignition and make sure nothing is loose enough to only make full contact when warm.
Good luck!

 

Start the car cold and while idling in neutral, wiggle all of the connection plugs to the fuse box. Put a special focus to those in the lower row along the bottom of the box.

If this is the problem source you will hear the engine pick up the extra bank of cylinders