sugar58

Please bare with me, I don't know all that much about cars (ya ya, woman driver here ...) So try to be nice! I have a 2001 V6 3.8L with 115k. I had some overheating problems some months back but fixed it with the changing of a sensor (not sure if that could be related at all). A couple months back, I hit a good bump and ripped off part of my exhaust and had it fixed with a new pipe (ya.... i know). Ever since then, my b/f seems to think I have a manifold (header?) leak because he can "hear the leak" and I've had terrible gas mileage since then. When I'm talking bad gas mileage, I'm talking like 260-280 kms (160-180miles) to a tank when driving in the city, when before I was getting about 500-550kms to a tank when I first bought it a year ago. Could an exhaust leak cause me to have such a terrible loss in fuel ? There are no visible leaks or holes that we've seen. This is what I've ruled out so far
1) Spark plugs newly changed
2) Fuel filter changed
3) Air filter changed
4) Oil recently changed
I've read a lot about it being maybe an O2 sensor, but I also read that if it were my o2 sensor, it would throw a code at me but I haven't had any engine light or anything. What could be my possibilities at this point? Bad wires? Exhaust leak? I have no idea... I'm stumped. My car also vibrates sometimes and makes weird noises, like a gurgling noise when you turn the car off which seems to be coming from around the passenger side, but who knows. My engine has felt boggy and not at its full potential ever since I got it, so I don't really know how it SHOULD feel. It also jumps randomly when the gears are shifting (it's auto). Any help at all would be appreciated... I don't feel like going to Ford and paying them $120/hr to look at my car. They are thieves!

MustangSally94

if you did the plugs you should do the wires just so they are around the same age... the exhaust leak could cause the engine to feel slow and boggy but so could your injectors being dirty. The injectors could also cause your MPG to drop, not sure about the manifold leak. Id take it to a shop if you dont know any mechanics

03shadow

are your tires inflated properly? my neon was getting like 3 mpg less because i didnt noice that one tire was down about 10psi. if there is a supposed exhaust (header) leak, then it would probably help to get that checked too

sugar58

I put fuel injector cleaner in regularly and my tires are all inflated properly. I will get the manifold leak looked at but Ford said that it would not cause such a substantial loss in fuel. I'm thinking maybe a fuel injector leak? Or maybe the fuel pressure is off and releasing too much gas? Any other ideas guys? Thanks!

sIx

I could cause gas mileage to go to crap, if air is being sucked into it while driving it will throw the O2 sensors off, which would throw things off.

sugar58

But if that's what it is, then why am I not getting a code for it? Would something like that NOT throw a code? Thanks for your help.

sIx

I'm not sure, I got new manifolds before they cracked (it's a common problem) maybe someone else that has had the issue will reply...

03shadow

yeah sometimes mechanics dont really know what they are talking about, but neither do we 100 percent of the time

Synyster06Gates

When my manifold was cracked, my gas mileage went to ****. I also got a code though, for one of them. I've had BOTH manifolds crack and it showed a significant drop in mpgs both times. The reason is because the o2 sensor reads lean so the computer tries to fix it by sending more fuel to the engine.

03shadow

would it be possible that hers isnt cracked bad enough trip a code?