Poor fuel economy on a 2002 toyota tacoma 4 cyl

Hello, I have a Tacoma with 69k miles on it, have replaced the spark plugs and had an oil change, and I am only getting around 14-15 mpg. I have no idea what is causing it. I drove on the interstate for about 30 miles @ 65 mph and went to fill up to see. Any help would be appreciated.

 

4x4 or prerunner or 5 lug? Manual or auto? What body style?

 

It isn't a 4x4, but what is the difference between a prerunner and 5 lug?

 

The number of bolts on each wheel.... 6 or 5

The prerunner is basically a 2wd version of the 4x4
the 5 lug is the mini truck

 

It has 5 on each wheel.

 

Ok, I would check the air filter and make sure all your plugs are getting spark. Does it run and idle smooth? How does it brake? Does it shift ok?

 

Brake and Shifting seems fine, it seems to run alright. I will try to see if all cylinders are firing tomorrow.

 

Ok, my guess would be one of the plugs isn't firing right. Did the mileage go down after the plug change?

 

I changed the plugs hoping that one of them was bad, it stayed relatively the same.

 

Coil packs? Any codes?

 

No codes, and didn't mess with the coil pack.

 

What plugs did you use?

 

Clean maf to.

 

I used ngk platinum plugs.

 

All spark plugs are firing, and the MAF is clean. The air filter is a little dirty, though. Can it really cause me to get that much less miles?

 

Not really but I try to change mine yearly. Maybe replace your fuel/air sensor. Before that, I would recommend dumping some injector cleaning in the tank (Techron concentrate)

 

Do a full tune up. Check your tire pressure. Get smaller tires. Check your manifold vacuum and do a compression test.

I also get around 15-16 mpg. Assuming the engine is in good order, there's nothing else you can do. It's not a Prius, it's a pickup truck and a 13 year old one at that.

 

I appreciate the help from the thread, thanks.

 

I would replace the primary o2 it's old even though you only have 69k miles. I get about 26-28mpg in my 96 4x4 with the 5spd and 2.7 when I'm on the road

 

You have a PreRunner, he has a mini with 2.4L. should be seeing mid-to-high 20's even with auto. unless you have a steel block for a right foot, or 300+lbs in the bed constantly.

smaller tires isn't the answer if they are stock, you'll get worse mpg if you start messing with ratios. the other tests I can see doing. check for leaks at the heads/manifold maybe seals are bad

that's some good hyper-miling!