Terrible, Terrible Mileage
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Join Date: August 23, 2004
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Terrible, Terrible Mileage
In the past couple of tanks I have been getting about 15-16 mpg down from 19-20... Last tank I got 180 miles... ![Icon Rolleyes](https://themustangsource.com/forums/images/smilies/icon_rolleyes.gif)
At idle it almost sounds like there is a backfire every once in a while. I pulled a couple plugs and noticed there was a white residue on them after only about a year of having them in since my head gasket was changed. I read that it could be a clogged air filter, and the guy at the parts store said that I should check vacuum lines.
Where are all the vacuum lines? Is there a way to test the plastic ones, or do I just have to listen to them and see if I can hear anything? Do you guys have any other things I should look for?
Thanks in advance.
![Icon Rolleyes](https://themustangsource.com/forums/images/smilies/icon_rolleyes.gif)
At idle it almost sounds like there is a backfire every once in a while. I pulled a couple plugs and noticed there was a white residue on them after only about a year of having them in since my head gasket was changed. I read that it could be a clogged air filter, and the guy at the parts store said that I should check vacuum lines.
Where are all the vacuum lines? Is there a way to test the plastic ones, or do I just have to listen to them and see if I can hear anything? Do you guys have any other things I should look for?
Thanks in advance.
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In the past couple of tanks I have been getting about 15-16 mpg down from 19-20... Last tank I got 180 miles... ![Icon Rolleyes](https://themustangsource.com/forums/images/smilies/icon_rolleyes.gif)
At idle it almost sounds like there is a backfire every once in a while. I pulled a couple plugs and noticed there was a white residue on them after only about a year of having them in since my head gasket was changed. I read that it could be a clogged air filter, and the guy at the parts store said that I should check vacuum lines.
Where are all the vacuum lines? Is there a way to test the plastic ones, or do I just have to listen to them and see if I can hear anything? Do you guys have any other things I should look for?
Thanks in advance.
![Icon Rolleyes](https://themustangsource.com/forums/images/smilies/icon_rolleyes.gif)
At idle it almost sounds like there is a backfire every once in a while. I pulled a couple plugs and noticed there was a white residue on them after only about a year of having them in since my head gasket was changed. I read that it could be a clogged air filter, and the guy at the parts store said that I should check vacuum lines.
Where are all the vacuum lines? Is there a way to test the plastic ones, or do I just have to listen to them and see if I can hear anything? Do you guys have any other things I should look for?
Thanks in advance.
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Jack up the rear end then put your car in n and see how easy the rear wheels turn. Engine off of course. I had a rear caliper hanging up and after I fixed that my MPG's increased. just a thought
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