This is a thread with a strange title since low gas mileage is and expected consequence of owning a minivan.

This is a 2010 but only has 37,000 miles on it. I replaced the plugs, plug wires, and coil pack last year after getting a misfire code. The repair solved the code. I also replaced the gas cap to fix a vacuum leak code. Other than that, this really hasn't needed anything.

The last several fills, it looks like I am getting about 11 mpg, which is pretty low. My notes say that I was getting more like 14-15. All of this is around town driving. I have had a few road trips where I got closer to 20 mpg.

Does the 11 sound low? If so, is there anything I can do about it? I will probably clean the throttle body and MAF sensor. I don't think this has a fuel line filter to change. I don't remember if I changed the air filter with the plugs but I will check. I could try a can of seafoam I guess.

Thanks for the advice,

LMHmedchem

 

I am not really sure about my method of estimating the mileage. At some point I will hook up my ODBII link to my laptop and see what it says when driving around locally. I looked it up and this van is supposed to get 17 mpg for city driving. That seems a bit optimistic but I still think that 11ish is very low.

Looking at the things that might affect the mileage,

- frozen brake caliper
- dirty throttle body
- dirty MAF sensor
- dirty oxygen sensor
- dirty fuel injectors
- dirty fuel filter
- poor alignment

I have checked the brake hardware and everything is ok. The front brakes are new.

I can clean the throttle body but I can't find a video for my engine (2010 3.3L v6). The throttle body on this engine doesn't look like any that I have ever worked on before so I am reluctant to just pull if off and spray it. Can anyone point me to a write up or video on how to do this on a 5th gen 3.3L engine?

I can clean the MAF, that is usually straight forward.

I would sort of expect that dirty O2 sensors or injectors would result in an engine code. Is this correct? What can I do to investigate this?

It doesn't look like this van has a removable gas filter.

I will get an alignment next week.

Are there any suggestions on any of this?

LMHmedchem

 

It turns out that one of my rear caliper brackets has a frozen slide pin and the rotor has become very warped. The pads looked fine but I should have looked closer.

I have ordered replacement parts to do the rear brakes and calipers. I may be able to do that tomorrow, weather permitting. I know that a frozen caliper piston can cause mileage problems. Can a frozen slide pin and warped rotor do the same?

LMHmedchem