fuel question

[chrissbee77]

I have a 2001 grand pridx 3.8 n/s and was just wondering if 355-371 is about right for a full tank of gas. i know that depends on tune up and how i drive just wanted someones opinion. i dont dogg it out and just replaced the air filter full tune up and fuel filter just thought i should be getting more mpg

[tblake]

355-371 miles per tank? I would say thats pretty much the norm.

[grandprixgtx00]

are you talking highway or city? i know on the highway with my GT i usually get around 34 MPG, and in the city usually right around 25. but yeah, for hwy right around 370 miles for a full tank of gas sounds right.

you can always check your MPG by filling up your tank, once its close to empty....fill it again and see how much fuel you used, then divide the miles you went by how many gallons of fuel used, theres your MPG

[wlkjr]

Sounds about right. I can stretch mine to 400 but why?

[doctorhrdware]

With my gp I get around 420 to a tank full, that is with out streching it. I am getting close to 32MPG. But it will very between 28 and 32 MPG.

[GTPSPEED]

wow, I wish I got that out of mine.

I get about 16.6 to the gallon.

[BNaylor]

Originally Posted by doctorhrdware

With my gp I get around 420 to a tank full, that is with out streching it. I am getting close to 32MPG. But it will very between 28 and 32 MPG.

Is that highway or in city? Too good for "in city only" and 20-22 on a GP equipped with a NA SII 3800 engine is normal. It should be higher for highway only like when traveling. Combined varies.

[richtazz]

I get 21-22 around town in my 99 GT and highway mileage varies quite a bit depending on speed.

I recently took a trip and did a little experimenting with very interesting results which actually validated what I thought before I started.

Once on the highway and at cruising speed, I reset the DIC at different speeds to see what effect it had on MPG.

At the start of the trip fully fueled in Michigan, I set the cruise at 75 mph (any less and you'll get run over on US-23) and got 27.4 mpg. I hit the Ohio border and dropped the cruise to 68 mph and reset the DIC and was getting 33.6. As i got further south where traffic was moving faster, I bumped it up to 72 mph, and still was getting 32.8. I filled up for the return trip home and repeated the experiment, and even with a full tank, I got 32.6 at 72, and still hit 33.5 at 68 mph, and dropped again to 27.6 doing 75 mph in Michigan. By this experiment, it seems these cars hit an aerodynamic wall at about 75 mph which affects economy quite a bit. Keep in mind that each figure was attained after a distance of at least 90 miles, some a little more, so I believe they are pretty accurate according to the DIC mileage indications for comparison purposes.

[grandprixgtx00]

Originally Posted by richtazz

I get 21-22 around town in my 99 GT and highway mileage varies quite a bit depending on speed.

I recently took a trip and did a little experimenting with very interesting results which actually validated what I thought before I started.

Once on the highway and at cruising speed, I reset the DIC at different speeds to see what effect it had on MPG.

At the start of the trip fully fueled in Michigan, I set the cruise at 75 mph (any less and you'll get run over on US-23) and got 27.4 mpg. I hit the Ohio border and dropped the cruise to 68 mph and reset the DIC and was getting 33.6. As i got further south where traffic was moving faster, I bumped it up to 72 mph, and still was getting 32.8. I filled up for the return trip home and repeated the experiment, and even with a full tank, I got 32.6 at 72, and still hit 33.5 at 68 mph, and dropped again to 27.6 doing 75 mph in Michigan. By this experiment, it seems these cars hit an aerodynamic wall at about 75 mph which affects economy quite a bit. Keep in mind that each figure was attained after a distance of at least 90 miles, some a little more, so I believe they are pretty accurate according to the DIC mileage indications for comparison purposes.

i did sort of the same thing with my GT. sounds about right. when i got on the 2 lane roads up in the UP Michigan and set the cruise to 62, my DIC said i was getting 35.6 MPG. here in WI the speed limit on the freeway is 65, if i set the cruise at 72, the DIC said i was getting 28.3 or something like that.

[jessep28]

I get about 19-20, but about 60% of my commute is in stop & go traffic.

[doctorhrdware]

That is both city and highway. In city it is usually around 23 give or take.

[wlkjr]

I was going almost 75 but the DIC only wrote me up for going 68.