Way to start off the week

MF1455v · Jan 27, 2004

looch, what year model is your Jetta? Did you add the heater after market?

I have a 2001 and did not come with a heater. On our extreme cold mornings here in North Texas /forums/images/graemlins/grin.gif about 32 degrees, it tends to grunt pretty good when starting. I have had it checked out several times and it checks out fine. It gets the same full my tractor and my Dodge Cummins does and they have no problems. Of course the tractor and the Dodge don't get 52 MPG.

Junkman · Jan 28, 2004

(
Junkman, when it gets really, really cold something happens with fuel. Exactly what that something is, I'm not 100% sure. What I can say is that on my Jetta (which has clear fuel lines) when it's this cold, and if I haven't added any fuel conditioner, I see little bubbles in my fuel lines. The engine does not appreciate this interruption in fuel delivery. I am assuming this is what was going on with my tractor. )

Let us look at this "phenomena" reasonably.... If you are getting air in the fuel lines in the winter, then why wouldn't you get air into the fuel lines in the summer. Air has to be introduced into the lines somewhere between where the fuel exits the fuel tank and the injector pump. If it is sucking air when the engine is running, then it will be leaking fuel when the engine is off. I don't know what you are seeing in the clear lines, but I am certain that it isn't air. If there is air in the fuel lines, then the engine will not run. I think that the person that suggested it might be wax has the correct answer. Wax forms when the temperature is cold enough to separate it from the rest of the oil. Adding a treatment to the fuel causes the wax to dissolve and mix with the additive which in turn lowers the temperature where the wax will crystallize again. If you were able to get the treated fuel cold enough, say -50 degrees Fahrenheit, it might just form wax crystals again. Hard to imagine, but it can happen.... air can't.... that is my story and I am sticking with it... /forums/images/graemlins/grin.gif /forums/images/graemlins/blush.gif

Mark_in_NH · Jan 28, 2004

( I do use additives in my car and I know they can damage the fuel pump because of a lack of lubrication. )

From what I have learned and can gather from reading the differant manufactures information, on the differant addatives available. Most good quality addatives available (power service) and I am sure there are others. They have the necessary ingrediants in them, to help provide for proper lubrication.