Ok so I recently put my entire car back to stock and i've been noticing my gas mileage is shitty. Before I had headers, exhaust, tb spacer, pulleys and a cai with a fresh filter. Now all I have is the cai with a fresh filter and my gas mileage seems to be horrible.

Car has 101k on it and im not sure if the plugs have been replaced yet.. what could be the culprit? o2 sensor (removing headers could of fuxed something) if its the o2 sensors do I need to replace both or just the primary? since the 2nd one doesnt really do much but monitor cat efficiency. I sea-foamed my car a couple thousand miles back, gas tank/through the intake manifold/in the oil. And I just changed my oil with fresh mobil 1 extended performance (claims to be good for 15k)

Prob a common thread but the words bad and gas dont work in a search.

Thanks for the advice.

 

give us the before/after gas mileage numbers

 

I honestly never kept track of mpg... but its a noticeable decrease

 

If you can't quantify it, then there isn't a problem

My guess is that you're in vtec more to compensate for the loss of HP from the mods

The ECU is also going to have to re-learn after removal of the mods too...

And if you're complaining after one tankful, you're going to have to wait to see if the mileage situation is longterm or caused by something like a bad tank of gas.

I've got a logbook with every tankful of gas I've ever put in my CL since it was new (71800 miles). I can easily tell when something is wrong if the mileage decrease and be able to calculate mpg loss to 2 decimals points

 

Try resetting the ECU, though.

 

damnnn thats impressive!

 

Wow man.. just like my ex. I think you people are crazy.

I just reset my trip meter every time I fill up. If I go less than 300 miles on a tank (not fully empty obviously) I will start to worry.

 

the engine also does not work as hard when you have headers and a pulley, so that will contribute some right there...

 

No i've actually been babying it and the car does feel like it has more torque without those mods. I reset my ecu after everything was taken off and than I reset it again last night, we'll see.

 

WOW seriously, im lucky to get 230mi in the city on a full tank. You must drive like an old lady bro. If youre talkin about the highway, then yeah that sounds about right.

 

i usually get 250-320 on all city, its okay to dry like a grandma. just bcus u have a quick car doesn't mean u drive like a maniac... lol. drive slow so ppl can stare.

Ya need to pump your breaks and drive slow homey

nuff said

 

I get about 23mpg (highway, with alot of stop and go). I don't like to use the "miles per tank" 'cause there are so many ways that can be interpreted. I've put in up to 16 gallons in the tank (we've got a 17g tank), but usually only put in around 13.xx gallons... (about 1/8 of a tank left plus the reserve).

I usually get 280-300 per "tank" with for me is 13-14gallons, so 21-23mpg. I've gotten almost 400 miles out of a "tank" too, but that was with the low fuel light on for awhile...

 

yeah 78000 miles here and I get about 20-22 MPG on each tank. If I take a long road trip it would average about 25 MPG going between 70-85 MPH


I do the same as green monster except for writing it down. If I get anything lower than 16-19 MPG on consecutive tanks then I know something is wrong

 

Wow so the average mpg people are getting is around 20ish combined city/highway. Damn I feel sorry for you people who have to drive all city, now that I think about it, lately my driving has been a lot of short trips around town and a few highway runs... im gonna monitor my mpg next fill up.

 

yeah, i drive like a grandma too, and usually get around 320-335 miles in city but if i punch it a little, lol i get around 275 miles. on freeway i get awesome mileage, around 435 miles on full tank.

 

See, highway sounds about right. I normally get 400 to 430 on a full tank. Its been awhile since i monitored my fuel consumption. One of my boys who works at a dealership gave me a nice oil additive for my oil change comin up.

 

dude, im lucku if i get over 230 with a full tank, and it sucks

 

damn that sucks.. I get about that mileage with still at least a quarter tank left

 

wish i had 6-speed

 

wow, I average 26 mpg. around 400 a tank city/highway in SF Bay Area. only thing I use is a K&N drop in.

 

I average out around 22-23 mpg per fill up for combined city/highway. That's a lot better than my truck which only gets 14 mpg

 

yeah I started to average 20-23 city/highway with headers and k&n drop in. also noticed I drive little harder then used too... oh well
my mpg sounds about right compare to some of u guys...