Honda Repair: fuel milage, honda civic 4dr, spark plug wires

Question
I have a 2004 Honda Civic 4dr EX.  I've been fighting gas milage.  This summer I was getting up to 36 mpg and now that it's cold, I've been getting 29 mpg.  A few years ago I was able to get 38-40 mpg.  Any ideas? The timing belt air filter, tires, plugs, wires are all newer. As i understand there's no inline fuel filter on this car. My honda seems to run and shift smooth. It's up to 190,000. I have had it serviced every 3000-5000 miles by the honda dealer and by the local mechanic and nobody can figure out where my mpgs are going.

Thanks!
Mark

Answer
Mark, tune-ups on these cars become more frequent when the milage goes up. But, it sounds like you have been on top of that maintenance.
Tune-up = spark plug wires, spark plugs - (properly gapped), distributor cap and rotor, air filter, and a fuel filter. Yes, this car does have an inline fuel filter. And if this specific component has not been replaced for sometime now this could be your culprit.

If you do not already always use Premium (Super) Unleaded.

If you are also looking to grab a few more MPG's you can look into a few bolt-on modifications. For instance a cold air intake will not only boost your HP (around 10) but, also give you a couple of MPG's. There are some dyno proven companies out there that test there products.