Ok, replaced plugs\wires\cap\rotor, and recently installed new headers, which i thought would help the milage. but before the plugs etc. i was getting about 13.5-14 MPG. and after i was getting the same. AFTER the headers, i was expecting an increase of at least 1 MPG.. nope, still getting 13 MPG and 14 if im lucky.. I can drive like an old women with no feet and I still get crappy millage. I seem to actualy get better millage driving it hard every once in a while. What should i go for now? Does igniton timming have anything to do with millage? Tire pressure is 32. HELP. should i replace EGR stuff? Im not getting any codes..

 

ummmm, maybe your injectors are off.....also...what about an 02 sensor?

 

I don't want to be technical man but I have a 5 speed and a baby 305 and only get 15 in the city. That is normal man relax.

 

I'v got everything in my sig and get 16 around town and 21 on the highway and this is with a carb. Definately check your timing i gained about 3 mpg once i got my timing right. Then check your sensors starting with O2 and go from there.

 

The mileage you are getting is not normal. I have seen over 30 in my '88 GTA (350) several times. Mostly in the high 20s for mpg.

The factory rated these cars at something like 17-18 in the city and 25-26 highway.

Headers do make the mileage better---IF you keep your right foot out of the firewall.

I don't know your problem but there is something wrong.

jms

 

the O2 is new. and i know that i can get better millage, because I HAVE GOTTEN 16 MPG before, when i first got the car from my uncle, and it slowly went down to 15 then 14 for the longest time, and now im getting 13..

 

Overall, how is your car running? When my car ran good, I got 17mpg. Currently, my car is running very rough overall and I am getting 11mpg.

 

it runs pretty good. idles nice, doesn't miss or anything.. im gonna try and get some specs tomorrow, fuel pressure, vacume, compression etc...