2000 4.0 p0172 p0175 codes

dogwalkin · #1 12-04-2012, 05:27 PM

Ok I am new here. I hope you guys can help me. I have a 2000 ranger 4x4
4.0 OHV. My CEL is obviously on and those two codes are what the code reader pulled up. I have ordered a scanner that reports data in realtime and will have it on friday. Till then I was hoping you could give me some hints. Here is what I have done so far.
Downstream o2 sensor
Mass air flow sensor
Checked all vacuum hoses.

The truck runs better than new. It idles perfect and accelerates well. If the light was not on I would not think there was any problem.
I also pulled the plugs and they do not show a rich condition like the pcm says. So if you got any ideas throw them at me.

Thanks in advance

reconjb · #2 12-04-2012, 05:35 PM

you may try checking out the upstream O2 sensors the downstream is mainly just to make sure the catalytic converter is doing its job

http://www.obd-codes.com/p0172
http://www.obd-codes.com/p0175

DustyXB · #3 12-04-2012, 05:42 PM

Check the wiring to your MAF also are you using a garbage K&N filter? If you are junk it and get a new MAF you can't clean them well not easily at least.

dogwalkin · #4 12-04-2012, 06:07 PM

Ok I have not checked the 2 upstream 02 sensors. I have checked the maf wiring and
I found some specs on a website that I used a multimeter to test the voltage as the engine was revved and and the voltage moved up and down with the engine speed.

Rangerman49 · #5 12-04-2012, 06:21 PM

Quote:

Originally Posted by dogwalkin

Ok I have not checked the 2 upstream 02 sensors. I have checked the maf wiring and
I found some specs on a website that I used a multimeter to test the voltage as the engine was revved and and the voltage moved up and down with the engine speed.

Clean your MAF anyway and see if the codes go away...

Use this stuff....

DustyXB · #6 12-04-2012, 06:52 PM

Lmao proven to add 4-10hp to the wheels?! That's awesome!!

Bob C. of Indiana · #7 12-04-2012, 07:47 PM

Quote:

Originally Posted by dogwalkin

Ok I am new here. I hope you guys can help me. I have a 2000 ranger 4x4
4.0 OHV. My CEL is obviously on and those two codes are what the code reader pulled up. I have ordered a scanner that reports data in realtime and will have it on friday. Till then I was hoping you could give me some hints. Here is what I have done so far.
Downstream o2 sensor
Mass air flow sensor
Checked all vacuum hoses.

The truck runs better than new. It idles perfect and accelerates well. If the light was not on I would not think there was any problem.
I also pulled the plugs and they do not show a rich condition like the pcm says. So if you got any ideas throw them at me.

Thanks in advance

Don't know if this article will help or not because it is not for a 4.0 engine..Is your gas cap good?
http://troubleshootmyvehicle.com/for...uel_trim_1.php

dogwalkin · #8 12-04-2012, 08:52 PM

I will work on some of these suggestions tomorrow. I also forgot to mention that when I remove the battery cable and reset the codes I can drive about 25 miles before the light comes back on.

DustyXB · #9 12-04-2012, 09:48 PM

Yeah because it takes about that long for all the monitors to run and the drive cycles to be completed