Great hiway milage considering..

[PalmerWMD]

1994 Q45t:

On a recent trip from Atlanta to Louisville, at elevated temperatures, elevated elevations(;)) AC "on" nearly all the way and speeds between 75 and 90 mph I got 21.0 mpg (admittedly running GA gas which is among the best).

Oh, yeah and a 4.08 rear end too (Speedometer/odometer corrected for rear end)

Fred...

[docsmile71]

wow...that's good. Without AC, I get about 20mpg highway (driving from NYC to Boston). With AC, I get about 10mpg city and about 15 highway.

What's the secret?

[Rex]

My road trips to the ATL and farther south from Cincy usually net me about 22 to 24, depending on AC and if the back windows are all the way down. Consistent 16-18 as part of my everyday driving.

Of course, I'm NOT running the 4.08 that I know of???

[PalmerWMD]

If you did you would know.It's usually a bit of a hassle to arrange to have one,The stock is 3.54 is memory serves.

Fred...

[PalmerWMD]

Many southern states have non reformulated gas which is much better for milage.

Fred..

[elwesso]

I get about 12-14 in the city, and 15-19 on the highway..... not bad for a plenum where I could clean it with a spoon, and non functioning knock sensors....... Not to mention crappy indiana gas.......

Edit- Ac is always on for me..... I always have it on AUTO, ill sacrifice a few MPG (besides, whats a few extra MPG in a gas guzzler) for the car to do the thinking so I dont have to!!!

[PalmerWMD]

Indiana gas is better than KY gas.Some residents of Louisville cross the bridge just to get it over KY gas.

I think it's your knock sensors that are doing you in.

Fred...

[elwesso]

Wow, you replied like 20seconds after I posted!!!

And if you havent seen my post in the online mechanic, the Q is getting new knock sensors/harness, and a plenum/TB cleaning!!! I cant wait to see that mileage go up, and the performance with it!!!! Youll never be able to take the grin off my face.... Plus it'll have a perfect interior once I get the leather done........:ylsuper

Ive been saving up for a while just to this, I hope nothing catastrophic happens after this!!!

[Jesda]

14 mpg city and 16 mpg highway for me. I know I need an injector rail flush done among other things to improve mileage and idle.

[elwesso]

You need some new chain guides is what you need!!!!

[Rex]

The guy who owned my Q before me traded a Ferrari for it and a Lotus Espirit Turbo. So, he liked cars and took good care of them. It wouldn't surprise me if he had upgraded the rear gear, but since it doesn't "pull like a bull" from a stand still, I'll guess he didn't. That and I get decent mileage.

[PalmerWMD]

Rex:Good deal.

It's always best to buy a used car from eietrh a known entthusiast or from a wealthy person.

Fred...

[Jeff Williams]

Alabama gas must be prety good, as well. I get 21 to 22 MPG, with the A/C in Auto, and the crusie set at 77 MPH. I do some in-town driving, but that is only about 50 Miles of the 400. I spend about $400 a month on gas (Premiun from the same Chevron station). I fill up Monday, Wednesday, and Friday Mornings, unless I drive more.

[rydwhite]

I thought that the Q would get better mileage than that. I am getting 21.5 in my G35 mostly in rushhour traffic on I-65 and dowtown Indy. I use the ac usually when it is over 85, which hasn't been very often this summer, at least not yet.

[Jeff Williams]

You gotta pay, if you want to play.

[Jason B]

I just went on a huge trip to Boston, about 1000 miles overall. I averaged about 23.5 miles per gallon and it rode great. These were just about ALL highway miles.

I think the ECU upgrade may have helped a little.

[AZhitman]

I don't get it - I'm still hovering around 16, regardless of the type of driving I do.

[float_6969]

It's cuz Arizona sucks! Seriosly though, have you checked the obvious like O2 sensor, clean intake manifold, injector flush, sensor check, ect? I get a consistant 20mpg w/this 240 where I got 25-28 in all my other ones. But this is a SOHC, bad O2 sensor, bad air temp sensor, and the dirtiest intake mani I've ever seen, But the car has over 200,000 miles on it, so I'm not real worried about it.