engine identification and timing belt info

Newby to TDI's here. Recently bought an 02 Golf GLS with 1.9l TDI and 5 speed. I am prepping to do replace the timing belt, but not 100% sure of the different codes I keep reading about. MK3/MK4,? What is that? I believe my engine code is ALH. Can anyone confirm? Car has 250k and no maintenance records I know of. Below is the kit I'm thinking about.


https://www.idparts.com/alh-timing-belt-kit-038109119m-p-449.html

Liking my 50mpg car and want to keep it going for a long while.

Your Golf has the MK4 ALH engine. That kit will get job done for you. That's the same kit I put in mine. I would also add a gallon of G13 coolant and a thermostat and o-ring to my order. You're going to lose coolant when you pop the water pump out, so you might as well change the thermostat while you're at it. Very simple, only 2 bolts. If you're unsure what coolant it has in it now, buy several gallons of distilled water to flush the old out with before adding new coolant.

Now that you got me thinking, get new harmonic balancer bolts too. The old ones will likely strip the head. If they do, find a good 12mm 12 point socket and hammer onto the head of the offending bolt, then use your 3/8" wratchet to get it out. Hope this helps, and good luck on your new car!