dandar Posted September 27, 2005 Share Posted September 27, 2005 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 ? Quote Link to comment Share on other sites More sharing options...
stevelaw Posted September 29, 2005 Share Posted September 29, 2005 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 ' lighton 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 ? ← Quote Link to comment Share on other sites More sharing options...
RicnDenver Posted June 24, 2008 Share Posted June 24, 2008 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. Quote Link to comment Share on other sites More sharing options...
carlosgv158605860 Posted January 23, 2009 Share Posted January 23, 2009 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 Quote Link to comment Share on other sites More sharing options...
TOYTECH24 Posted October 20, 2011 Share Posted October 20, 2011 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. Quote Link to comment Share on other sites More sharing options...
XRumerTest Posted January 17, 2012 Share Posted January 17, 2012 Hello. And Bye. Quote Link to comment Share on other sites More sharing options...
00Tacoma Posted January 19, 2012 Share Posted January 19, 2012 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. Quote Link to comment Share on other sites More sharing options...
00Tacoma Posted January 20, 2012 Share Posted January 20, 2012 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? Quote Link to comment Share on other sites More sharing options...
TOYTECH24 Posted January 20, 2012 Share Posted January 20, 2012 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!!!!!!!!! Quote Link to comment Share on other sites More sharing options...
TOYTECH24 Posted January 20, 2012 Share Posted January 20, 2012 Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.