Toyota Repair: stalls while idling or driving!, auto parts supplier, aftermarket sources

Question
1983 Toyota p/u 4wd. 22R 113kmi. All engine original. Timing
chain replaced about 30kmi ago. Fuel filter replaced about the
same time.

2 issues, may be related?

1. Once in a while it will refuse to start. If I reseat all the
sparkplug cables into the distributor and to the coil, it'll then fire
right up. I've had the distributor cap and cables replaced.
Original coil. I will mention however, sometimes even after the
routine of reseating, it won't start. A quick spray of ether down
the throat of the carb, and it will fire right up.

2. Daily issue. After the engine is at full operating temp without
warning it will idle rough. I'll have to tap the throttle to keep it
going, then it'll clear up. However, shortly afterwards, the engine
will quit without warning. It's as if I turned the engine off. It will
do this if standing still or whilst with throttle on the freeway.
When it is at throttle however, it will start right back up without
any help. It seems it will quit for only one complete cycle, and
because it's rolling and ingnition is on, it starts back up. It may
exibit this once maybe twice in a day. Some times it won't have
the problem at all. I've tried to recreate it to troubleshoot but as
expected, it won't cooperate.

I may have a couple of problems not related, but...
sometimes I do get the feeling I have a fuel issue but most of
the time it acts like an electrical issue.

I'm close to just replacing parts until the problem ceases
throught the process of elimination, but where is it I should
most likely begin?

Answer
Distributor problems are common, the pickup coil can develop high resistance with temperature increase and cause a loss of spark to the spark plugs, I would try replacing it first, they are available from aftermarket sources, check with your local auto parts supplier.