Why is my gas mileage so bad?

I have a 2000 Honda CRV and I'm almost just giving up on this car, I love the SUV but I no joke barley get 200 miles to the tank, with this mileage I could be driving a truck or a Toyota 4Runner (which is what I really want), I changed and did the following: air filter, fuel filter, inflated tires, O2 sensor, rebuilt transmission and catalytic converter. The spark plugs and timing belt are fairly new and in good condition. I have invested enough money in this car to last another life time, I even took this car into firestone to check what was the deal and they said the car was in great condition, I understand this car is 17 years old but its only a 4 cylinder and in good condition

What is the MPG. Did you buy it used? Why put so much money into it? Just put it into the extra gas.

For the four or five grand you spent on random parts, you could have gotten enough gas to go for a couple of years. So it's not the savings you want: it's the bragging rights.

Telling us you get 200 miles per tank means nothing. How big is the tank and how much gas is left when you fill it?

You need to compute the actual miles per gallon. To do this fill the car until the pump shuts off automatically, do not top it off beyond that point. Reset the trip odometer or write down the miles on the car's total odometer. On your next fill up repeat the process of filling to the automatic shut off then divide the number of miles driven by the number of gallons you just pumped. Do this every time you get gas and keep track of the typical mileage. Variations of 1-2 mpg from one tank to the next are normal.

Your car is old so nothing about it is as efficient as it was when brand new. Just because its a 4 cylinder engine doesn't mean you'll get great gas mileage, if the engine is under-powered for the weight of the vehicle it has to work harder to accelerate which means it ends up running faster and staying in lower gears longer. This is why similar models of cars often get about the same fuel economy even with different engine options.

The bottom line is that you should do the basic things like check tire pressures and drive reasonably. The car might not get as good of mileage as a new car but the overall cost of ownership is lower because the car is so much cheaper. It would cost you more money every month to make a car payment on a new car vs just buying more gas for this old car.

The specs say you have a 15.3 gallon tank which at 22mpg should give you a 300+ mile range.
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How much do you put in when you top up?
Check your tires, are they the correct size and inflated to the correct pressure.
The car looks like a tank, is the weight of a tank and no doubt drives like a tank.
Revise you driving style. Get a lighter right boot. Avoid heavy breaking, or any braking wherever possible. Cut out harsh acceleration and read the road better.
Don't let the engine idle for long periods, turn off the A/C
Remove all the junk from the trunk or wherever it's stored.

Makes me wonder if there isn't resistance somewhere in the drive train. Differential or brake caliper/s hanging up.

Missing wheel alignment and checking the brakes. And excess slippage of the transmission. If all that checks out then it is the way you drive. Find out what the MPG claim is by Honda. You will never make the claimed number.

You mash the gas too hard. Stop and go is increased because you keep running up behind slower cars. Cool it if you want 30mpg. Leave some of that heavy stuff you don't need at home.

All Honda motors have a common problem with the valves getting tight and they need to be adjusted every 60,000 miles. When was the last time you had the valves adjusted? Tight valves cause a lack of power, poor idling, ad bad gas mileage.
Did you put NGK or Denso spark plugs in when you changed the spark plugs? Those are the only brands that can be used in an Asian motor.

Driving habits, no doubt.

How many miles on the engine?

Rub a white paper towel inside the end of your tailpipe. Is there black soot on the paper towel? If yes, then you are running rich, wasting fuel. Find out why.

-Engine overhaul mechanic and general automotive mechanic since 1972

p.s. Barley - barely

Try the changing the ignition wires, fuel pump could be bad, filter. Check the valves