I was trying to heat wvo for use in my 1.6L N/A Rabbit and I used a Bosch gp from the Rabbit and a tee fitting. Even at idle, that Rabbit pushed enough fuel through the fitting to completely cool the glow plug. As soon as I'd stop the motor, the gp would heat way up. Start the motor again, and it cooled right off to damn near nothing. I was hoping for about 150F, but wound up with a little more than ambient.

Your mileage may vary.

Chris Boyer
San Diego, CA