i have a 92 hatchback with a d15b7, all stock. it has lost about 10 mpg and the idle has gone up about 200 rpm. what should i do about this.

 

I'd say either take it to a shop or give a little more information cause no one's gonna bother to help with the lack of info you gave. Not trying to be mean at all (in case it came across that way) but you gotta help us so we can help you.

First off, if you're not familiar with cars and you don't currently have a competent friend/relative who is, then bite the bullet and take it to the shop. If in fact you are at least somewhat car savvy, then please provide us with the following info and anything else you think might help us help you figure out what's wrong.

- Manual or auto?

- What rpm was it at idle before the increase? Need to know if it was at a good idle to begin with. Also, has the weather changed and/or you using a/c now?

- Has anything been done to the engine lately? Including routine maintenance and/or light/heavy repair. Any new noises, vibrations or anything else that happens now or happened before you noticed these problems?

- Did your mpg drop instantly or was it over some period of time and how long if so?


Post back and hopefully someone can get you some answers.

 

yes i know how to work on my car and i am quiet farmilar with hondas. its a M/t. i never use the a/c so i dont think thats the prob. i dont have a tach so im no exactly sure how much it went up. it just feels around 200 rpm. no engine work has been done. it started to rust out the pipe that went to the muffler and thats when the idle went up so i replaced all that.

 

Check your cooling system for any leaks. Have you replaced your thermostat? I would also do a full tune up.

 

yea im gonna do a full tune up tomarrow, and ill check over the entire cooling system.