Should I use any additives in a Jetta tdi

We move a a lot of Stanadyne Performance Formula. It’s has everything you’d want and only adds about 10-12 cents per gallon to fuel cost. Most guys find they get enough mileage improvement using it to more than pay for it.

Amazing stuff for sure.
Have used this for about 100k it is worth four times the cost or at least it is in the '06 6.0, 178k original injectors dilution just about where it was when new-in an E450 rv the engine is derated to about 140 hp depending on who you speak with. Fortunately I am not too far from a D&W diesel store where the cost is about 20% less than the best online offers, or it was when I picked up a case in July of '22 of the 16 oz bottle (the size that treats 60 gallons); the fuel and oil filters are even a better deal.

Don't know if the additive is compatible with the def engines.
 
If you have a off road diesel pump at a fuel station nearby keep a few fuel cans in your car to fill up. You can add the fuel to your car at home.
and, if you get caught, there is a pretty good penalty. When I was farming I had diesel delivered to our farm tank. It has red dye in it and that dye lasts a long time. It never went into cars or trucks except in an absolute emergency. That happened twice, once in my car and once in a friend's. One gallon each time.
 
and, if you get caught, there is a pretty good penalty. When I was farming I had diesel delivered to our farm tank. It has red dye in it and that dye lasts a long time. It never went into cars or trucks except in an absolute emergency. That happened twice, once in my car and once in a friend's. One gallon each time.
I know of the penalty but i am saying many have done it for a long time. i know of a friend burning a blend of filtered WMO mixed with red diesel in his mechanical jetta and rabbit.
 
An additive isn't necessary. However, I've always used one in the 4 diesels I've owned over the decades.
4 advantages to using a good fuel additive plus one recommendation for emergency use:
  1. Added lubricity is good for the pump and injectors. (I never fell for the ULSD doesn't lubricate the pump myth though)
  2. Keeps moisture out of the fuel prevents icing and algae growth (algae growth is bad, been there, hated cleaning it up).
  3. Increased cetane can make the engine a little less noisy/rattley. DI is noisier than IDI in my experience, so it won't make it go away completely.
  4. Anti-gel if it gets really cold. Winter diesel is usually good enough at that, but extreme cold or poor fuel can wax up/gel from some suppliers. I don't really need it in the MD DC suburb area.
  5. Diesel 911 should be in your trunk if there is a chance you could get gelling or ice in the lines in the Winter. I don't need it in MD DC suburbs. I only use Exxon/Mobil. Shell, Citgo, or Sunoco if that's all that's around. Petro and Love's on trips.
I started with Power Services. Switched to Amsoil additive when I was a fanboy. Using Hot Shot's in the current DPF DI equipped MB now. Considering trying the store/generic brand at Tractor Supply.
You'll develop preferences based on your needs.
 
Last edited:
What myth? It is a fact that the lubricity standard for ULSD in the USA is significantly worse than what the Bosch pumps were designed for.
The myth is that there is no standard and that US ULSD doesn't have lubricity requirements.
I stated that added lubricant is good for the pump. I don't have a VW anymore, so don't follow their pump requirements.
 
The myth is that there is no standard and that US ULSD doesn't have lubricity requirements.
I stated that added lubricant is good for the pump. I don't have a VW anymore, so don't follow their pump requirements.

VW has never produced a diesel injection pump.

Bosch however has produced hundreds of millions. I’d probably follow their expertise, which is that North American diesel out of the pump is garbage. Their common rail fuel systems last 2-3x (literally) longer in Europe than they do here.
 
VW has never produced a diesel injection pump.

Bosch however has produced hundreds of millions. I’d probably follow their expertise, which is that North American diesel out of the pump is garbage. Their common rail fuel systems last 2-3x (literally) longer in Europe than they do here.
Great.
 
I always thought that an additive does in fact rid the system of excess moisture but only by keeping it suspension so it can be flashed off in the cylinders rather than collecting in the bottom of the tank where the organisms can multiply/party-does anyone know of any treatment which contains a biocide ?
 
I always thought that an additive does in fact rid the system of excess moisture but only by keeping it suspension so it can be flashed off in the cylinders rather than collecting in the bottom of the tank where the organisms can multiply/party-does anyone know of any treatment which contains a biocide ?

They treat water in two ways, they either emulsify it so it gets burned as if it were fuel, or they de-emulsify it so that it is large enough that the water separator can deal with it.
 
Back
Top