Any ideas on what it could be.

My milage has seem to drop???

 

what car is it? I am guessing it is the one in your sig. Maybe you have a dead cylinder or the injectors are clogging and not spraying right. Could also have a clogging cat or something like that. What have you done to it, and what have you tried so far? Anything else that you noticed other than the drop in mileage? Stumbling, power loss, knocking, excessive brake wear etc...

 

Are you throwing any new check engine lights? An Oxygen sensor on its way out will mess up your mileage...any sensors dealing with their air/fuel mixture ratio that go out will mess your mileage up...is it a real bad drop or just you seem to burn more lately? Do you have #'s or no?

 

hmm i got really low gas mileage on my car 2... i was looking through the console and i dont think its the injectors with how many recpeits i found where they were mentioned.. i got about 225 to the tank when i got the car.. i slight increase with the K&N... i drastic decrease in city with flows and a drastic increase on highway with flows 200city/300highway (WTF!) and i know the cats clogged i would enjoy the 300 in the city!

 

I went from about 240 - 200

Maybe my O2 sensor is going out.
I'm pretty much catless.

It seemed to clear up a little after I put some injector cleaner in.
But no where near 240....

I'm confused???

 

When my O2 sensor started going, the car ran really rough..had a bad shimmy to it..and it ran like crap. Gas mileage sucked too..and I'd occasionally throw a code 13..lean exhaust at warm cruise from O2 sensor... Replacing the thing totally did the trick. Made a HUGE difference..just you've GOT to reset the computer after you do it. Doesn't seem like a big deal, but it is..my computer FREAKED at the new O2 sensor..ran like **** for days and threw a CONSTANT Manifold Air Temp sensor code for no reason until I killed power to it to let it completely reset.

 

How much is one of those bad boys....

 

$20 and change at Autozone for the Bosch OEM.

 

That's common. What usually happens is the O2 sensor becomes contaminated and constantly produces a voltage reading below 400mV because it can't "sense" any fuel. In turn, the ECM sees the low voltage and thinks the motor is running VERY lean so it DUMPS fuel into the motor causing the motor to run like total ***.

Was your O2 sensor black when you pulled it out?

 

It wasn't all black, but it had black on it in like a scorch pattern..out from the center. I figured I'd see a good improvement with the new sensor, although I wasn't expecting the computer to react the way it did.

 

I would look at the O2 Sensor and possible vacuum leaks.

 

I'll check it out tonight...

Hopefully that is all it is....

 

If it's not the O2 sensor, well, at least it's one less thing you have to worry about later. And btw, once you take the original out, plan on throwing it away..don't look at it and if it looks new, put it back in, because chances are, you broke the thing taking it out. They're wicked sensitive, gotta be REALLY careful taking them out and putting them in. When I pulled mine out, I gave it to a friend who was running without an O2 sensor in his Trans Am to solve as a quick fix until he scrounged up some bucks for a new on....he got it in and had to remove it because it didn't work at all. And I was as gentle as I could be with it.
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And hey KJ, in your user info section on the pic of your car...I see a distinct outline of headlight covers? Where'd you get them/who makes them? I bought some up at Autozone, the Auto Ventshade kind, just simple smoked ones, and they had MAJOR overlap on both sides, like 3/4 in...I returned them. Do yours fit right in the cutout??