djkron

i have had this 4runner for about 4 months, love the frigging thing, deadly 4x4 and stability. The only thing i hate is that i am getting roughly 350km (217miles) to a tank. 17.2 gallons or 65 litres. runns really rich and chokes my passengers but i love it, i have put platinum plugs in, mobil 1 synthetic and new air filter, no change.
any ideas?
tune the comp?
bad injectors?
bad sensors?
bad maf?

HELP

az4x4runner

Sounds about right to me. I love mine and would never trade my bad gas mileage for another vehicle. I wish I got 217 miles to a tank, but I don't do much highway driving.

infiltrator

dude, 217 is perfectly normal IF NOT better than NORMAL :]

im lucky if i get 200, (but my spark plugs were bad and i just changed them)

stupid_mud_gremlins

I don't know about yours, but my timing is way the heck off (guessing a stretched t. belt). Can't adjust the EFI as far as I know, but for mileage, I'm only getting between 130 to 140 miles on a tank.

elripster

Can you fill out your signature so we know where you are located? You are on the low end of what one would expect a properly running 4runnerin San Diego to get. However, in colder climates, that's not the case, especially if you do shorter trips where the engine takes a while to warm up. Make sure to list what mods the truck has as far as tires, gears, etc... By the age of our vehicles, many are not stock and most mods affect mileage.

Frank

infiltrator

get that timing belt fixed asap. if that breaks, your stranded, and you could **** your engine.

stupid_mud_gremlins

Got a goodyear on order through work, should be in next week.

swaycleveland

since owning my 4runner and reading these threads ive ben watching my fuel milage im getting about 240 to 275 mile per tank which from what i can see is great for a 3.0 auto i have done the box mod new plugs and adjusted the timing which i can tell you helped alot and ive got 202090 on the speedo!

Belize Off Road Team

sounds like you all have low mileage! i get around 400kms to a tank! more on the highway. and i run 10W40 regular Texaco oil, regular TOYOTA spark plugs. K&N air filter, fram oil filter. no hood deflector, no sun roof wind deflector. etc etc...

SEAIRESCUE

"runns really rich and chokes my passengers" you got a problem. May be a failing O2 sensor. When mileage drops, for reasons other than E10 fuel, the first suspect is the oxygen sensor. It may not be throwing a code but I would replace the sensor. While at the parts store, see if one of the goobs will scan to see if you have any codes and if so, what are they? I presume yo air filter is clean? Air pressure in tires? I removed my spare tire and tools to save weight. I carry a bicycle pump and a nail plug kit.

My $0.02

stupid_mud_gremlins

I've got a code 21 (o2 sensor) on my 1st gen, would that possibly make my mileage get that bad (130 - 140 miles on a tank)? If I clear the codes the engine light will stay off for a while (longest is about a week). I'm still gonna put the belt on either way though. Seems like a good idea at just about 200000 Niles on the motor (3.0)

djkron

thanks guys, i am going to check out the o2 sensor and will get back to you, the pcv valve is brutal to get to and i plan on replacing that, should i also do a seafoam treatment.?

djkron

hi guys i checked the o2 sensor out, there are 4 wires coming from it 2 black a white and blue, if i tested it correctly (blue wire) read at no more than .12v. now if i understand it correctly i have a faulty sensor that is providing a lean signal to the computer which in turn will increase the fuel flow, causing the rich mixture. I followed the line running from the sensor to under the hood where i found only one black wire connected to a terminal block which was inturn connected to the positive on the battery, i believe this to be the sensors pre heater. the remaining wires are on the harnes that passes along to the transmission. which i assume travels to the ecu.

is this correct?

djkron

is this correct?

Jay351

I can't conferm the o2 sensor wiring but you can however get OEM replacments at www.sparkplugs.com I got a perfect fit NTK (ngk) o2 sensor for 38 bucks shipped.

As for fuel economy, im getting around 320 now (400 in the summer) I have yet to install my o2 sensor, but I noticed DRIVE like an old lady, im dead serious. You will save SO much gas. I was driving like an idiot these past few days, taking it up to 4k really giving her at stop lights, I got HORRIBLE mpg now. So just an idea.

stupid_mud_gremlins

There's a decent write up on testing an O2 sensor at:

http://wiki.answers.com/Q/How_do_you...h_a_volt_meter

I usually skip the part where it tells you to ohm out the connection between computer and sensor harness. I believe when I tested mine the signal was a brown wire, but mine's an 89.