gas milage problem (for long time now!!)

[willembron]

Hello all,
I would very much appreciate some help with my problem of gas milage!!! I live in Honduras (Central America).

I have a:
- 4Runner 4WD SR5 (V6 3.4L)
- from 2000 (one catalytic converter)

Since a couple of months I have a increased gas consumption... in the city I have now 10 mpg... on highway 15 mpg

I moved a couple of months ago to a city at 3000 feet (above sea level) with plenty of hills an small and steep curves and so increased gas consumption is ok but 10 mpg is not normal anymore and unacceptable.

Everything started when I move to this city and changed o2sensors (when those error codes came up)!

I have:
- changed the 2 O2sensors OEM (since those codes were identified, no check light anymore!)
- cleaned Mass Air Flow Sensor (MAF)
- changed all oils (engine runs ok!)
- Green air filter, recently cleaned (not too much oil put)
- no "check" light coming up now!
- cleaned EFI
- new spark plugs (OEM)
- cleaned injectors
- ...

I went to a mechanic (quite knowledgeable for Honduras ;-)) which who we worked everything through but no bettering is seen!

Gas is of bad quality in Honduras and low octane (but had no problems during 1,5 years) and had a aprox. 15 mpg normally!

How do I proceed? What do I do more, different?

Please help!

Cheers,
Willem

 

[RonMAIDEN]

Check the TPS and check the condition of the cat since some can slowly get clogged but not completely.

 

[NViejeP]

I live in San Francisco where theres a lot of hills.

I have changed my 02 sensors in order to help get me more gas mileage but it has yet to show any effects.

I usually get around 150 miles to a full tank, so it translate to like 10 MPG city. I don't drive too much highway, but when I do, I don't get that much better.

At first I thought I had a problem, but I tried everything and I have come to accept the fact that my car sucks for gas, unless someone can prove me wrong.

Ever since I bought it almost 2 years ago, I have yet to be able to get past 12 MPG city.

 

[LINY4Runner]

<cough>Tire pressure?<cough>

 

[shootmymime]

wellim thinking multipul things, if it runs fin then prob not a MAF or clogged fuel lines, it would have a rough idol or misfire.

so that said i would wonder when the last time u changed ut oil? sludge? it dosnt take much to screw a car up!

cats rarly get clogged, so i dont think so,

if u are saying low octane in your gas, can u get boosters?

good luck buddy!
thats my 2 cents

 

[NViejeP]

Well for me, I'm due for an oil change, but regardless of oil being new or not, my mileage wasn't affected.

At first I was almost sure that it was my fuel-ratio sensor (02 sensor) but I changed it and it hasn't helped.

 

[willembron]

Thanks colleagues (RonMAIDEN, NViejeP, LINY4Runner, shootmymime) ...

I appreciate... this issue drives me crazy!

Some quick response to your queries/comments:
- I hooked computer on again and TPS work fine!
- according to computer the cat also is ok!
- tire pressure is fine (265/70-16 Bridgestone Dueler) as it should be
- no misfires nor rough idols
- nor sludge... change oil regularly (every 3000 miles or 3 months aprox.) and I maintain a visual on the quality when changing the oil.
- accelaration is perfect, good reaction and shifting and ECT is working also.

So, the search goes on as I (still) cannot accept the fact that my car sucks for gas....

I like this 4Runner... its just perfect for the family and as I do some offroad because of my paragliding activities... no other car offers this... in my opinion... but for my environmental conscious and my wallet I will have to look for answers!

Cheers and I appreciate your thoughts!

Willem from Honduras