Can't seem to figure this one out. Usualy I get around 230 mpg but after washing my engine bay (trying to keep the car wash cleaner off all electrical stuff) now I get horrible gas milage. I just read the codes and it is the same codes it was throwing before. Catalyst, secondary air injection malfunction. It is due for an oil change it has been 3k miles since I bought it. Any ideas. I thought I might have messed up my maf but no code for it. Any help would be great

 

Sorry I mean 230 miles per tank to 130 on a full tank to gas light coming on

 

You mean per tank not mpg lol try new plugs wires filter oil fuel filter etc and see how it goes

 

WOW! 230 mpg!!! That's awesome! Take that Chevy Volt! And Toyota Prius!

 

O2's might be wet causing a lean condidtion. Maybe? My car does that sometimes when it rains, but it'll spit and sputter.

 

Reading your title I was like GOOD GOD WHAT THE **** AM I DOING WRONG!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

was the engine hot when you washed it ? could have cracked the intake manifold causing a big vacuum leak.

 

But wouldn't that make his car idle at very high rpm's?

 

Join the club, I've been getting about 100miles per tank for about a yr. Been told I need to change the headers bc of an exhaust leak, needless to say, I ordered the headers on april 29, and after a few issues, still waiting on them . WTF

Goodluck

 

Man after seeing some of your guys mileage, I guess I feel good. I freak out if I get any less than 250 to a tank. And that's an LT1 car.

 

LT1 gas gauges were guesstimate gauges. Freeway/city mix I would fill up at 1/4 tank mark, mine would get about 200-215 miles off 12.5 gallons. So imagine off 15 gallons I would be some where near 250, that was with a 3200 Vigi torque converter. Good times, I miss daily driving it.

 

yep my lt1 gas gauge goes up to about 1/4 past full. Ive heard that once it gets down to about full then you are at a half tank, at half tank mark you are a lil more than a quarter, and when it is on empty you better be at a gas pump or you'll be walking.

 

haha my lt1s the same way. i usually fill up around 1/4 mark at 220-230 miles. usually fill up around 12 gallons or so

 

I fill up around 14 gallons if I run it dry. I'm at around 275 on the odometer. 250 is around 12 gallons.

 

hit 26 mpg on my way to Houston a couple weeks ago cruising from 90 to 110mph. Only got 18 on the way back cruising @ 70-75mph. That will change once I get a new rear end with 4.10's though.

 

the motor wasn't really hot when I washed it and I kept it off the block and hand washed it later when it was cool. I'm stumped. I'll give it a tune up this weekend and see if it helps.

 

Thank God I have a 3.4 v-6. I get about 26 on the highway, usually around 350 miles to the tank. That is about 3 days worth of fuel. All that with 270,800 miles on the clock.

 

My car ran like crap due to headers and good ole Mikey set me up with a nice set of Kooks.

 

Did you check all your fuses/connections? I know I popped the fuse to my MAF one time and it stayed in startup rich mode and drank the gas.

 

Are your cats good?