14mpg? WTF?

[johnwc723]

well this has been a continuing issue with my car that i have never been able to fix, for some reason i get about 14mpg in my manual lxi. (140k miles) i have replaced the oil and stuff and even the injectors but this is really wierd shouldnt the car have like twice that, on a tank i only get ~200miles. anyone had a similar problem or have any idea why the hell my car is soo rediclously inefficient!?

[goldyaccord]

Fuel leak maybe?

[shepherd79]

did you check your ECU? does it give you any code?

[TINBOAT]

Does the car run rough?....also, do you have the proper thermostat ?...the economy of our cars depends on alot of things, but engine temperature is very critical to fuel management...there are things to check, such as idle air control, electrical connections, but most of these are actuated by coolant temperature....make sure you have a 195* thermostat.

[johnwc723]

my ecu is fine it seems and the car dosent run rough, i did just replace the thermomenter last summer. could my car be soo out of tune that this is happening or is that out of the question and still have it running?

[johnwc723]

yeah and the fuel isnt leaking i mean i had big problems with that earlier and you can really smell it if it is!!

['A20A3']

Check you air and fuel filters. You might wanna check your plugs & wires too, while you're at it.

[k-roy]

Quick question. What brand and grade of fuel do you use?

[johnwc723]

i have a CAI new plugs and fuel filters

['A20A3']

Another question, do you run you car hard? As in do you run it in high RPM ranges very often?

[MrBen]

Do you drive like an ass? Do you buy crap gas?

[Blkblurr]

Check your oxygen sensors and your atmospheric pressure sensor. These are directly responsible for air/fuel mixture. Do you notice black smoke coming out of your exhaust? You may have a plugged catalytic converter but you should notice a power loss if that happens.

[TINBOAT]

my ecu is fine it seems and the car dosent run rough, i did just replace the thermomenter last summer. could my car be soo out of tune that this is happening or is that out of the question and still have it running?....

What temp is your thermostat ????
what does your temperature guage read ??

[Blkblurr]

Your thermostat, if stuck open, can cause a mild amount of fuel economy waste but not 50%. It could be a combonation of things though.

[johnwc723]

i drive very modestly due to my terrible gas mileage i never really hit 3k much unless i really need to accelerate, a wierd thing that happend this summer is my car was overheating to shit (well the temp gauge said it was) so i replaced the thermostat and took out all teh sesnsors and cleaned them off with sandpaper now rarely does the temp gauge ever get above zero. dont have any black smoke at all coming outta the exaust. the o2 sensors are on the exaust right? whats the atmospheric temperature sensor?

[Blkblurr]

Atmospheric pressure sensor measures the oxygen content in the air. You should not sand the sensors, especially the oxygen sensors. There are two oxygen sensors on the exhaust manifold. They cost about $25 each to replace new. Have you lost power???

[johnwc723]

i dunno my car has always been like this, i dont know i would have to have another 3geez owner drive my car i guess heh. well i sanded the temperature sensor right by the thermostat, it had a little build up on it so i figure why not, it prolly ddint make any difference... i wonder why i never get up to anything above zero temperature tho, (well i do if im running for a LONG time)

[TINBOAT]

replace your thermostat and bleed the cooling system...from your post, your temp guage is operating...it is VERY critical to have these cars running at proper operating temperatures...just cant stress this enough...BTW, my 89 LXI auto gets 28mpg in the city, and 33-35 on the highway, and I dont pussy foot the car either.

[Blkblurr]

I agree with changing your thermostat. Make sure it has the same temp rating as the original one. My 89 SEi gets about 27 city and 32 highway and has 230,000 miles on it. Your engine and fuel system was designed to run at temp so don;t mess with the thermostat temp by putting in a lower temp one than what the car came with. I think it is around 190 to192 degrees F

[k-roy]

WHAT TYPE OF GAS DO YOU USE?

[johnwc723]

normal 87octane shell gas! heh nice caps this sucks now that i really want to fix it its in the middle of the winter, yeah i do have the 192 thermostat in there, i know they are really easy to replace just very cold out at the moment, i wonder if that could be the root of my problems? theres gotta be something else wrong too i bet.

is there any way i can tell if my atmospheric pressure sensor is good, or the o2 sensors (i dont get and check engine at the moment which means they must be somewhere in wack?)
thanks guys, maybe soon i can save $20 a fill up! jeeze

[k-roy]

Try better gas and see what happens.

['A20A3']

My Baby only gets 89 or better.

[johnwc723]

dude dosent only premium help if you have a high compression engine? it shount make any difference here!

[Blkblurr]

Better gas will not help milage because added octane only makes it harder to burn. I use the same gas in my 89 SEi and get 27 -32 mpg. I still think your cat is plugged. the only way to test the sensors is to use a voltmeter and follow the procedure outlined in the Honda service manual. Is it possible someone is draining your gas?