dandar

code P0171 on 2000 4-Runner

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After having two Toyota Dealerships analyze the ' Check Engine ' light

on our 2000 Toyota 4-Runner, they each came up with differing

answers as to what needed to be done based on the fact that

their computer showed up a Code P0171

Can anyone advise what code P0171 actually means ?

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That code is for "lean", as in the air/fuel mixture. Stick your finger up the tailpipe and wipe the inside. What color is the ask inside? Is it gray? That would be too lean. If it is black it's probably not. Also check your spark plugs.

After having two Toyota Dealerships analyze the ' Check Engine ' light

on our 2000 Toyota 4-Runner, they each came up with differing

answers as to what needed to be done based on the fact that

their computer showed up a Code P0171

Can anyone advise what code P0171 actually means ?

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Steve is right, its running lean. if after cleaning the MAF, replacing the PVC and cleaning the Throttle body and plugs, if the code comes back, you will need to get a new MAF. there only about $80 and you can install that yourself.

http://www.4x4wire.com/toyota/maintenance/...ntenancep5.html

ALSO, at about 100K miles you will want to change the O2 sensors.

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I have a 4Runner 2000 SR5 v6, 97.500 miles, same problem, I change the sparks plugs, O2 Sensor before catalitic, clean MAF sensor, check for vacuum leaks, erase code and after 2 hours Check Engine light again P0171.

I'm going to change the fuel filter and add a injector cleaner.

Any advice.

Thanks

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check your fuel pressure. misdiags are being down. saying maf sensor is issue. its not. take ur maf sensor off the air filter box/air filter box tube. get volt meter....test the sensor by blowing air into it. if u have a can of computer aerosol dust cleaner thats the best to use. lightly blow into the sensor.....then do a quick full shot of air.....if u notice the sensor fluctuating on the measurements.....sensor is good. then check your fuel pressure.......it has to be right on the money as far the specs for fuel pressure.

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check your fuel pressure. misdiags are being down. saying maf sensor is issue. its not. take ur maf sensor off the air filter box/air filter box tube. get volt meter....test the sensor by blowing air into it. if u have a can of computer aerosol dust cleaner thats the best to use. lightly blow into the sensor.....then do a quick full shot of air.....if u notice the sensor fluctuating on the measurements.....sensor is good. then check your fuel pressure.......it has to be right on the money as far the specs for fuel pressure.

TOYTECH24,

How do you check the fuel pressure. I'm having the same issue, but what is strange is that my check engine light comes on when the tank is almost "E", then I will fill it and with in a couple of days it will go off by itself, it's a vicious circle.

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That code is for "lean", as in the air/fuel mixture. Stick your finger up the tailpipe and wipe the inside. What color is the ask inside? Is it gray? That would be too lean. If it is black it's probably not. Also check your spark plugs.

I have the same issue, my light comes on and off depending on how full my tank is. almost @ "E" it comes on, then when I fill the tank it turns off after a couple of days. Had MAF cleaned and checked, O2, fuel filter, new plugs, ect. Any ideas?

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with a fuel pressure gauge is how u check ur fuel pressure. find ur fuel rail. should be a plastic "tire cap" and unscrew it. u'll see what looks like a tire valve/schrader valve and screw ur fuel pressure gauge adapter to it. turn key on KOEO (KEY ON ENGINE OFF) and see what gauge reads. if at first there is no fuel pressure......and gauge reads zero......try starting it. at which time u should have fuel pressure. if it was at zero when u did KOEO........ur fuel pump is bad!!!!!!!!!

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