Major gas mileage drop after 6 bolt swap question?

[SexyGsX]

Swapped a 6 bolt swap in and before my gas mileage was about 21 mpg. Now I get only about 14.5 and I was not really pushing it hard to see what it could be. I have gone through two full tanks and it is about the same. I know it shouldnt be this bad. I have checked for any leaks and none. I have a leak at the throttle body shaft seals and have a new throttle body to put in. This small boost leak should not be the only factor causing this. My car also stalls sometimes for no reason and seems to be at a loss of power, I know due to the boost leak, but a friend said I might be running really rich. I dont have an air to fuel ratio guage so I dont know. How could I find out if I am, and what would I do if it was? Please and thanks in advance!

 

[Flash]

A fix that has worked for me for many different scenerios is to disconnect the battery and that should reset the ECU. Then reconnect it and see if it worked.

 

[SexyGsX]

I'll try it, but I have done that while adjusting some other stuff. I dont think that is my problem though. Any other suggestions from anyone. Thanks though.

 

[94Jettameowpsst]

Maybe its a 6 bolt thing....haha, every car i've owned has had HORRIBLE gas mileage, but my 2g was getting around 24mpg. Check all your basics, timing, plugs, coilpack, fuel pressure regulator, gaskets, etc. Any of those things will reduce your mileage.

 

[SexyGsX]

New coil packs, wires. I will be checking the timing tomorrow although I am pretty sure that is not it as I just had it done. How do I check the fpr?

 

[2gredspyder]

Could be a bad 02 sensor.

 

[Injected]

Could be a bad 02 sensor.

Would have thrown a code. Fix the problems you know you have, then see where that gets you.

 

[2gredspyder]

Would have thrown a code. Fix the problems you know you have, then see where that gets you.

Thats not always the case.

 

[SexyGsX]

Brand new o2 sensor too. Throwing my throttle body on right now, we will see after that. Still any other ideas, would be greatly appreciated. Thanks again all!