I finally have my Scan Gauge II calibrated correctly. With my new injector nozzles, I was able to calibrate it correctly to match my fill-up gas mileage calculations. My old injectors leaked so I could never converge on calibration the Scan Gauge II correctly.
Fall hit along with heavy rains and wind. It seems that the effect of rain is about a 8% - 10% hit in gas mileage reduction. Here are my last week's mileage numbers with the new Bosio DLC 250 injector nozzles. 60 - 63 mph average commute driving 35 miles each way.
day--------to work(mpg)--to home(mpg)--daily average--notes
10/31-----50.8------------52.7-------------51.75-----------heavy traffic home
11/1-------55.6-----------56.1--------------55.85-----------Daily record high
11/2-------50.6-----------55.5--------------53.05------------ -
11/3-------51.8-----------51.6--------------51.7------------ -
11/4-------50.3-----------57.3--------------53.8------------ gusty tailwind home
I didn't record which days had rain, but those appear to be the 50 mpg trips. Morning mileage is worse, as it gas mileage takes a big hit until the car warms up. This year tdi has a coolant heater that draws about 80 amps to get the coolant up to temp for emissions. It takes big draw on the alternator and a big parasitic draw on the motor. When I start the car it is running at 0.27 gph at idle when cold for about 5 miles. When it is fully warmed up at idle it is 0.16 gph - 0.17 gph, so the parasitic effect of the alternator draw is obvious. I shoot for 1.0 gph on level ground while driving (60 mpg) so the alternator draw is about 0.1 gph or a 10% reduction in gas mileage.
I had some wastegate or boost leak problems this week. I lost boost going up a hill, then regained it, then noticed boost pressure being about 2 psi higher during cruising speed. So, maybe a waste gate issue or boost control? Or a boost leak fixed? or a boost leak created? Going to check the intake tubing today. I used to cruise on level ground at around 16 to 17 psi (absolute pressure). Now it is about 18- 19 psi (absolute pressure or MAP), but gas mileage is the same. I am now going to do the famous Italian TDI tune up every day at least once to keep the waste gate from carboning up and sticking. A full throttle short run everyday to keep the carbon away.....