2001 Jetta 1.8T, 100K miles. Smokes when hot.

If that bottom hose is cold, it sounds like the radiator itself is not circulating.

check the ring and piston

Usually a sign of piston ring wear...also to costly to repair this condition in this motor...better off with a used replacement motor with fewer miles...ALSO, you can limit the exhaust smoke if it is still running OK for you...Visit your auto parts store and review...add oil additive...Many brands and not to costly...This is probably your least costly repair so you can still enjoy your
Celica...Hope this helps.

How many miles on engine?. What color smoke? If white clouds of smoke that goes away when it warms up that indicates a possible housing seal. Another symptom would be having to add coolant. view this video -> https://www.youtube.com/watch?v=4H-B1nckyFE

This smoke, where is it coming from? is it coming from engine area or under the car or out of the tail pipe?what color is the smoke?

A lot of miles on this beast. check carefully and unless a REAL bargain...walk away.

Timing Belt replacement ....When and who? Every 100,000 miles is service interval.

Reason why they are selling it...... Problems or just getting a newer car ?.

Smokes on start up cold?

Smokes warm idling ?

Smokes after coast down and then accelerating ?

Warm start okay ?

Drive shaft boots not split ?

Does transmission jump out of any gear?

General condition ie: accident damage, tyre wear even, tested recently ?

Brakes stop car without pulling to one side.

Does car drift off center along a straight road above 30 mph?

Seat belts operate ?

Steering gear loose or worn? Must be less than 5mm free play side to side on steering wheel at 12 o'clock..

Steering wheel solid mounted...lower support bearing okay ? They drop out around the steering shaft.

All lights work including high and low beam?

Brake lamps working?

Windshield free of cracks and chips and not scored by old wipers.

Pull up carpet and inspect for corrosion in floor pan and in trunk ( boot.)

over 100k miles bad oil sending unit, bad crankshaft sensor
and you have a bad relay for the fans or the plug is burn inside get under the car and pull the fan plug it is under the driver side

the problem will be faulty injector tips squirting and not atomizing take it to an accredited diesel specialist shop and have the new tips fitted and the injectors recalibrated

If its when you start it cold its probably valve stem seals,as the oil runs through them overnight and dumps in the cylinders when you start it cold and it smokes,if its smoking when hot or warm and when you rev it its probably piston rings,you didnt say how many miles are on the car,even try thicker oil and a new filter to help

this is a common problem for these cars glow plugs go bad like spark plugs however the smoke would lead to bad mass airflow meter. it is not telling ecu corrcet miss. disconnect mass airflow meter. when cold see if this makes it start better. it should would means you need new m.a.f. glow plug issue take a test light place clamp on positive of battery then pull off glow plug connectors place tip of test light on glow plug the bad one will have a dull light unlike the good one which will be brighter. will need new plugs and wire harness four **** connectors and wire striper and crimper will fix concern good luck