Poor mileage after being out of service

[bryansr]

I just got my Explorer back on the road in late December from when the transfer case failed last March..... Yeah, I know, took a lot longer than it should have......

Anyway, before it went down I was regularly getting 16/18 mpg around town and 18/20 highway. Now I'm getting a solid 12 to 13 around town. Any suggestions on what I should check? I'm going to change the fuel filter, just waiting for better weather to do it..... Thanks.....

 

[rb142]

There's a big difference in temperature, fuel blend, etc. between March and now that can account for part of that. But that still seems like a big drop. (You didn't switch to an Ethanol blend fuel did you?)

I assume you don't have any codes set? Lacking any other clues, I would start by checking out the coolant temp sensor and the oxygen sensors for proper operation. If you have a scan tool with live data, check to see that it is going into closed loop.

 

[bryansr]

Not unless where I fuel up changed because I'm filling up at the same places I did last year. No, it hasn't thrown a CEL. I will look into how to check the CT sensor & O2 sensors..... Thanks

 

[drdoom]

Make sure the airbox is clear, mice and what not.

 

[koda2000]

Make sure the airbox is clear, mice and what not.

That was exactly the thought I had. Mice will get in there and fill the air box up with all kinds of stuff. I've seen it happen more than once.