Let us know what you've checked already, if you have.

So many issues can be the cause of poor mpg.

In terms of issues particularly more common on the prelude that I know of, check your:

• timing belt tensioner
• distributor
• O2 sensor

Also, is the car burning oil? (lol duh) How much?
Valves adjusted?

Common causes:
- air filter needs changing

• spark plugs need changing

• fuel system needs cleaning? (you've been using premium fuel as the engine requires, yes?)

- low tire pressure
- coolant system thermostat needs changing

Start with the simple/cheap fixes first, and move up towards things that need changing as part of maintenance anyways. Start with the colored items.

Lastly, this is just me ole opinion based on some light experience and research, apologies if none of this helps

 

Let us know what you've checked already, if you have.

So many issues can be the cause of poor mpg.

In terms of issues particularly more common on the prelude that I know of, check your:

• timing belt tensioner
• distributor
• O2 sensor

Also, is the car burning oil? (lol duh) How much?
Valves adjusted?

Common causes:
- air filter needs changing

• spark plugs need changing

• fuel system needs cleaning? (you've been using premium fuel as the engine requires, yes?)

- low tire pressure
- coolant system thermostat needs changing

Start with the simple/cheap fixes first, and move up towards things that need changing as part of maintenance anyways. Start with the colored items.

Lastly, this is just me ole opinion based on some light experience and research, apologies if none of this helps
[/QUOTE

Let us know what you've checked already, if you have.

So many issues can be the cause of poor mpg.

In terms of issues particularly more common on the prelude that I know of, check your:

• timing belt tensioner
• distributor
• O2 sensor

Also, is the car burning oil? (lol duh) How much?
Valves adjusted?

Common causes:
- air filter needs changing

• spark plugs need changing

• fuel system needs cleaning? (you've been using premium fuel as the engine requires, yes?)

- low tire pressure
- coolant system thermostat needs changing

Start with the simple/cheap fixes first, and move up towards things that need changing as part of maintenance anyways. Start with the colored items.

Lastly, this is just me ole opinion based on some light experience and research, apologies if none of this helps

This is the first I noticed, I haven't had a chance to check many of these potential issues. The spark plugs are only a few months old, I have not checked the thermostat, but the radiator was replaced this month. The car did have to be rebuilt and the valves needed to be cleaned, because of low compression. That was done several months ago. I have been using premium. This was the first time I filled my car after the radiator was changed

 

Definitely have a new air filter if that hasn't replaced in a long time.