1998 Vw Beetle TDI ?

Question

Do i need to put any treatment in my car. Its is a 1998 VW Beetle TDI with 125,000mi.

Answer 1

ask "a car nut"! he has a lot of  experience!

Answer 2

No, in fact VW recommends against and fuel additives of any kind; having said that, it has been my experience that there can be cases where it won't hurt, and may in fact, help.

If the diesel fuel sits in the tank for long periods of time, it can grow bacteria in the fuel (regular diesel fuel, I don't know about bio-diesel, don't have enough experience with it), so if the vehicle is going to sit for a while and you don't want to drain the tank, then some additive designed to kill the bacteria in the fuel would be helpful.

I have enough experience with diesels over the years:  Owned 1979 Rabbit Diesel bought new; Puegeot 504 Diesel, 1978 Oldsmobile diesel, Ford Escort diesel, and Nissan Diesel pick up truck and there is  at least one other time you want to add something to the fuel, when the temperature gets close to zero F and you have diesel #2 in the tank.  At this point, diesel fuel is close to becoming a gel and doesn't flow hardly at all, so you need to add something to the fuel the improve the flow.  You can get winter additives to add to the normal diesel fuel (if the fuel isn't labeled as #1 diesel or winterized diesel, then its #2 diesel fuel), or add a small amount of gasolene to the fuel to improve the flow or get a block heater to help the diesel flow better, by increasing the temperature of both the motor and indirectly, the fuel.

There is one last method of dispersing the wax in normal #2 diesel, but unless you have experience with this I don't recommend it at  all:  you can heat up the fuel tank and get it hot, which will get the fuel flowing..  (I won't tell you how I used to do it when no other possible remedy was easily available!).

Well, I hope this helps, a car nut.

Other situations can arise, like a sticky fuel injector; it either drips or doesn't have the correct spray pattern (bad enough for a gasolene motor, absolutely terrible for a diesel), some additive designed to clear clogged injectors can help and save money (injector replacements on a diesel aren't cheap).