I havent taken much notice on my gas mileage, I rarely drove my car because I was unemployed for awhile. I recently got a job and I filled up my tank Saturday, drove probably 50 miles total since and i'm at a half tank already. I haven't been in boost, I usually drive on the HW most of the miles at about 70-75, so 3100rpms.

I recently got into an accident, I had slight damage and chassis damage in the trunk. Crash beam took most of the damage, left side tail doesnt sit right. Neck flapper on the gas tank must have broke off and fell into the tank or something... I'm not sure if there would be any damage to my fuel pump or not..

Car idles at about 1.2k-1.5k depending on how it feels.. Idles cold at 2k. I had a full boost leak test Mid Dec and held 33psi. Just recent shaft seals put in the TB. When I got into the accident I threw an EGR code, I reconnected my battery and it hasn't come back yet.

Can anyone think of what the problem could be? I have been doing research for the past 2 1/2 hrs. Some things I could think the problem could be...... Long list.

IAC - Fuel Pump - EGR Valve - EGR Solenoid - MAF - Cam timing?

Idk, i'm at a loss. Hoping I can get some input on this. Thanks.

 

Do you have a wideband? If so, what AFR are you at when cruising?

Have you checked behind the intake manifold if any of the EGR vacuum hoses have popped off? Shouldn't account for the bad mileage but if you got an EGR code might be worth taking 5 minutes to check.

 

ARF's im anywhere between 14.6-15.9. I have checked the hoses and they are still on.

 

O2 sensor? That'd be my guess.

 

Nothing obvious like a gas smell around the car when it's off signifying a leak, right?

 

Only time I smell gas is when it's idling.

 

AFR should be way off if it was the o2 sensor.

 

my afr's are right where they should be...most of the time. but i have a sensor that barely puts out more than 1v so my trims are rediculous and it will throw a cel if i dont keep it shut off in the periphery.

i get like 12mpg around town and 23 highway though.

 

Fill it up to see if it really is half a tank down.

 

Wise man..... by half tank, do you actually know how much fuel you put in? just saying, your gauge could be wrong. Also, the fuel tank probably has a number of vent tubes, hopefully none of them popped off or something, broke, etc.....evaporating gas is another thought, we are all assuming its not leaking fuel?

I knew someone with a mustang that has a crack in their tank, but it didn't leak until they went around corners and it sloshed around. Something you wouldn't notice standing still.