Another thread about crappy mileage

[toms89]

Now I am getting a check enigne light with code P0155.......any idea which one of the sensors it is.

This is what the code comes up as: 02 Sensor Heater Circuit Malfunction (Bank 2 Sensor 1)

Bank 2 is the drivers side & sensor 1 should be the upstream or 1st O2 sensor. (Bank 1 is the bank that the #1 cylinder is located on which happens to be the passenger side on the expys.)

I forgot to add....one sensor is a Motorcraft and the other is a Bosch. I am being told that this could be the problem. Anyone ever heard of that?

This should not cause an issue as long as the correct matching sensor is used but you can't go wrong with OEM.

 

[bar422]

Just ordered another motorcraft sensor and it should go in later today. I can't believe a new ones would cause problems like this but the guy working on it said he has had it happen where 2 different brands don't play nice together......I'll keep the group updated on what happens.

 

[Raoul1219]

Ok i justgot my expy last week. Have not done some real testing of the fuel economy, but my in car system tells me i am at 15mpg for haigway and city. And on the 2 long hiway trips i did, i reset it and hit 19 and 20mpg at 57mph cruise control. I think thats really not bad, you think the reading is inacurate ?
I got a 1997 4wd 5,4

I wounder how the towing numbers will be, for a small horse trailer, see pics

 

[bar422]

Well according to what the code said it was the Motorcraft sensor that was bad......it has been replaced with another one and I haven't seen the check engine light come back on yet.......but I am going to wait for a few days before returning the other one just to make sure.

I did have a guy tell me to try and run some higher octane fuel for awhile and see if that helps at all....anyone tried this for mileage? I usually run ethanol but I have heard its not all its cracked up to be.

 

[toms89]

Well according to what the code said it was the Motorcraft sensor that was bad......it has been replaced with another one and I haven't seen the check engine light come back on yet.......but I am going to wait for a few days before returning the other one just to make sure.

I did have a guy tell me to try and run some higher octane fuel for awhile and see if that helps at all....anyone tried this for mileage? I usually run ethanol but I have heard its not all its cracked up to be.

Higher octane fuel will not increase mileage unless the tune is adjusted for it (more ignition timing). Or if its experiencing detonation and retarding the timing.

Cannot run E85 unless you have a flexfuel expy. The tune and likely fuel system would have to be modified for it. You can make more power with E85 but will get less mpg. But then its cheaper than gasoline.

 

[bar422]

I think I will just stick with the 89 grade that I have been using....I think that's what the manual calls for anyway. Mine will not do E85 so I wasn't even thinking about that. If the oxygen sensors being replaced doesn't fix this mileage thing I don't know what else to do.........Anymore input is appreciated and thanks to those who have responded!