is there anything to do about gas mileage?

[BoWzER]

and ideas how to get better mileage out of and auto xr?

[merkurdriver]

Only drive downhill in neutral?

Just the same as any other car, a good tune up and proper tire inflation will yeild better mileage.

[milehighXR]

Don't drive it like you stole it, bump base timing to 13° BTDC, let off the gas as you go downhill/approach lights, and shift it into neutral(engine still running) on LOOOONG downhills. I have gotten 25.85 MPG out of my auto XR with 20° BTDC base timing and these tricks(see my sig for mods), on 91 gas. It no runs booze

[bw_krupp]

Drive by the vacuum gauge, never use your brakes, never shift into neutral (it takes more gas to keep the engine idling than it does if you are coasting and the momentum is helping turn the engine). Every action you do in the car think about how much load you're putting on the engine and how to avoid it. I've gotten 36 mpg out of my 5 speed merk. ~32 avg.

The best tip is to drive it a week with bare feet. Makes you that much more sensitive to what your car is doing.

[salukixr4ti]

buy a Honda

[milehighXR]

Bare foot good idea. Not shifting into neutral bad on long downhills. I've hit 65mph going downhill in neutral. If you have a manual and you're really good you can shut the motor off in neutral while going down hill, and then pop the clutch to restart. I haven't tried it, but sounds neat. Momentum is not turning the engine in an auto XR, just gas... Oh yeah you can put an A4LD in it...

[BeefFajitas]

Shutting off the engine while the car is still moving equals dumb idea.

[cooperl]

make sure the sensor ground is connected to the compressor housing. i'm pretty sure this will effect closed loop operation. you would prolly notice if it wasn't...

[anglin]

Not shifting into neutral bad on long downhills.

Maybe you're only talking about an automatic transmission-equipped car. If you let off the gas completely at any rpm above about 2000 (I think it's more like 1800, but I don't recall exactly) the fuel injectors shut off until the engine rpm drops below whatever the critical rpm is. So, if the engine is turning 3000 while you are cruising and you lift off the gas pedal to coast down, no fuel is being injected until the engine drops below the critical rpm. If you put it in neutral and let it idle, you may take longer to coast to a stop, but the fuel injectors are injecting fuel to keep the engine idling.

Try it sometime. You can hear the injectors come back on. This doesn't occur until the engine is warm enough to operate in closed loop. If the engine is in open loop the injectors will still operate above the critical rpm with the throttle closed.

Another key is to keep the engine in closed loop on the highway. The engine management system switches to open loop at around 3000 rpm under cruising conditions. You can stay below 3000 rpm to keep the engine in closed loop by driving slower, or installing a taller 5th gear or rear differential gear. Or you can get a J3 chip burned that raises the cutoff from 3000 rpm to some higher value (like 3500 or something).

Coasting is key, which really blows because I prefer the haulassthenbrakehard approach to driving.

[xrian]

Bad ideas from above answers:

#1 Driving bare foot
#2 Shuting of engine while coasting
#3 shifting to neutral while coasting
#4 BUYING A HONDUH!!!

[bw_krupp]

Bad ideas from above answers:

#1 Driving bare foot
#2 Shuting of engine while coasting
#3 shifting to neutral while coasting
#4 BUYING A HONDUH!!!

I take exception to #1. Legally you can only drive while wearing shoes or barefoot, so you can't do it with only socks. Driving bare foot makes everything much more sensitive if you're trying to drive economical. And unless your feet are greasy or the pedal covers are missing, you're not going to have a lack of grip. This is a trick I learned when I first started driving and any car that is new to me I drive at least a few days with bare feet to get a feel for the car. Every car I own I get better than stated mileage out of it because I learned how to drive it, rather than hopping in and going.

[John Brennan]

Best thing to do, although one of the hardest for sure, is to tighten the nut behind the wheel...

[Rotisserie]

HA! good one...
if you have EEC tuning equipment, you could also raise the close loop threshold. that'll help tremendously.

[Ed Lijewski]

One thing I've noticed in recent months is that the differential price between premium and regular gas has consistently been 17 cents--in my area at least. So, as the price per gallon of gas has risen, the, um, premium one pays for, um, premium, has declined. Granted the decline is hardly anything to note, but it makes filling up with premium rather than regular that little bit easier to take.

YMMV

[Larry Velk]

We have so-called 'reformulated' gas in SE Wisconsin; it is 10% ethanol in addition to other manipulation. Counties in Western Wisconsin sometimes have 93 octane which (at times) isn't reformulated and the premium sometimes has MTBE rather than alky. With my son driving - with my supervision - at legal speeds with this 'better' gas, we get 22 - 23 versus 19 with the _hi_ gas, same conditions. The wife's '89 used to get 23 - 24 in summer with the old style gas some 15 years ago. These are C3's. The T5 with SVO 5th ratio and auto rear only gets 20 with the _hit gas on the highway. Son JUST got his license and drives very conservatively. Mileage on these cars not their best feature as both our Porsches easily beat them. My theory is they are too rich for safety reasons (pinging). I bet guys with the laptops are doing better.