Passat 2005 Running On Used Soy Oil And B100

Tbe dealer had my car for 6 days. Each day I had to call them and ask them what was going on and each day they told me they were "running diagnostics." Well what about the oil leak I asked that's easy to see. "We don't see an oil leak," they said. What?! I have a stained driveway and a nice wad of newspaper soaked with oil. Well what about the check engine light. "The engine light is not on," they said. Steam was actually coming out of my head at this point I was so angry. I flat out told my representative that the mechanic must have reset the engine light, which I had done myself only a couple weeks ago after I cleaned out the air filter and watched the light come back on after a couple miles, because it had been on for weeks. The rep said he wouldn't have done that. I said, "well what about the acceleration problem." "The mechanic can't figure it out because there are no codes or engine lights." I told them, "You suck." And I picked up my car. The only good part of this story is that my rep decided not to charge me the $200 diagnostic fee after I repeatedly pointed out that they did NOTHING to diagnose it.