Suggestions on how I can improve my MPG on my commute??
 

Here is pretty much my route (Of course, I’m not going to post my exact house or work address)-
http://www.mapquest.com/maps/92064/4...park+rd+92036/

Can’t get more out of my trunk. I have to keep my fire fighting clothing and boots there. I keep the tires at 36psi.

I drive a 08 Honda Civic Automatic. I have a scangauge installed. I do a good job in anticipating traffic lights and I don’t speed up when someone is riding my butt. I start (home) at about 500’ and end at work at just above 4000’. I know where the hills and curves are so if I’m heading downhill, I’ll know where to let up on the accelerator so I won’t need any braking while hitting this stretch of downhill. For uphill, I try to gain enough speed to make it up part of the way without having to hit the accelerator , however, I’ve been finding lately very slow moving semis and cement trucks, so I pretty much now just figure accordingly to not hit the hills so fast. For my last downhill stretch prior to work, I shift the civic into neutral and when I get almost to the stop sign (I’m going around 4mpg, I shift back into drive.
That is pretty much it-

I’d appreciate any suggestions. Thanks.

BTW, I've been averaging very high 30s and very low 40s on the commute.

Not too shabby! 3500' is a big elevation change and it takes energy to make it happen. You've already made the biggest adjustment to the nut behind the wheel. :thumbup: Without alternate routes available you have to start working on the car. Try inflating your tires to max recommended on the sidewall. Then you can move on to the simpler aero mods like a grill block.

Keep up the good work!:thumbup:

Your best bet is to do the grill block and make a partial belly pan for it to bridge the gap (if there is one) between the bumper and the front of the chassis (usually where the engine is mounted). That alone will give you a pretty good improvement on millage. When Car and Driver did it back in the 70's they attributed most of their millage gains to the air dam they made and the partial grill block. they were able to go from 14mpg to around 18mpg at 70mph. But that was also with a few other small changes as well.

High 30's in your car is doing nicely! That's 25% over EPA.

What are your goals?

One technique I'd investigate is popping into neutral rather than coasting in gear.

I would not recommend coasting with the engine off in your car (1) because I'm not sure if it can be flat towed (ie. whether the tranny would be damaged by extended coasting with the engine off), but more importantly because (2) the steering in the new Civics is brutally hard without assist. Far more difficult than some larger vehicles I've driven.

It might be due to the fact that they've also got tiny steering wheels. :)

One thing you might try is blocking the radiator on the downhill - if it's all or mostly downhill. Use a piece of coroplast (the stuff they make political signs out of) or similar. Use the ScanGauge to monitor coolant temps. The point is that going downhill the engine is under little load, and so doesn't produce much heat. The airflow may cool the engine way below optimum operating temp, and the engine computer may even be burning extra gas trying to maintain a minimum temp.