Fuel Milage....

Turbo Tim · **Posted:** Sat Jul 17, 2010 11:54 am

Is it just me or does the fuel just go to crap in the summer time? Seems like my mileage goes down every summer. Even in my VW TDI the mileage goes down.

So I guess the real question is does this happen because the fuel is crap, or is it because the air temps are so high (especially here in Phoenix)?

Is there an additive to help?

Ya I know the AC is on all the time too!

barnez224 · **Joined:** Fri Jan 19, 2007 11:28 am **Posts:** 130

That's very strange...I usually get better mileage in the summer than the winter (around +5 or 6 mpg). When it starts to get cold, they typically use additives in the fuel to reduce gelling which lowers mileage. Although, in Phoenix, I'm not sure if winter even exists!

Big Montana · **Posted:** Sat Jul 17, 2010 1:22 pm

My MPH goes up in the summer too... then again, I'm out of school and I drive more highway, and my thermo has been bad for two-three years. I would think summer is better mpg.

RAF 3829 · **Posted:** Sat Jul 17, 2010 3:07 pm

I've always see a drop in the winter, not in the summer.

stoutdog · **Posted:** Sat Jul 17, 2010 3:16 pm

Tim,

I don't think we get winter fuel in Phoenix.... I think we get the same fuel mix year round. Running the AC on full blast all summer, as we have to do here, is probably the reason you are seeing your mileage go down.

LibertyCRD · **Posted:** Sun Jul 18, 2010 10:36 pm

MPGs are horrible here in the Winter compared to Summer too.

And for the record, I can confirm that running the A/C kills the fuel economy. I was running all week at 28-30 MPG on the EVIC.. turned the A/C on today and the EVIC started dropping like a rock while on the HIGHWAY with the cruise set! This reminds me why I try to avoid using the A/C at all costs.

geordi · **Posted:** Mon Jul 19, 2010 12:37 pm

I almost never have the AC off, so it doesn't show to me as much... But at the same time, this is a diesel. The less-than-1-HP that the compressor needs shouldn't be affecting the mileage that much. I wonder if you guys are having something else, like the computer is cutting back on the performance b/c of the heat detected?

kjfishman · **Posted:** Mon Jul 19, 2010 2:04 pm

Winter blend fuel in the northern parts has anti gel additives that reduce economy. St. Louis gets some pretty hot weather and we don't notice a big change in fuel economy. Now that I have over 90k the fuel mileage seems to be getting better, the engine must just now be broken in.

racertracer · **Posted:** Mon Jul 19, 2010 10:26 pm

Or the other scenario could be that the fuel supply is being splashed with biodiesel which benefits the suppliers bottom line, causing the end users MPG to drop.

runningbird · **Posted:** Sat Jul 24, 2010 2:04 pm

My dodge trucks with Cummins diesels have always gotten better milage with higher temps.
But to my suprise our little jeep does not, on a trip from Phoenix to the west coast we left in 114 degree temp. at 75mph could not get the evic to get past 30 mpg. stopped for fuel in Yuma and hand calc was 27. once in CA slowed down to 70 and once the temp got below 95 our milage went up. finished our drive with the evic at 35.5. filled up and hand calc at 31.7 mpg.
On the way home it was cooler in az and the whole eastbound trip ended up at a hand calc of 31.3.
So I think the Jeep just does not like the temp over 110.
just my thoughts.

Big Montana · **Posted:** Sat Jul 24, 2010 2:59 pm

I would love that fuel economy. I just got my first 27.9 mpg the other day (hand calc) and I was over the moon. I know that the speed and temp was a huge issue. It was cooler so I kept AC off and it was storming the whole way, so I was around 65-70 MPH. I noticed the RPM gauge was near or below 2000 most of the way. That seems to be the cherry speed with my neutered TCM.

Fuel Milage....

Who is online