× Help us help you. By posting the year, make, model and engine near the beginning of your help request, followed by the symptoms (no start, high idle, misfire etc.) Along with any prevalent Diagnostic Trouble Codes, aka DTCs, other forum members will be able to help you get to a solution more quickly and easily!

jeep liberty 2004 3.7 trouble codes 0172 and 0171 at the same time

  • overdrive138
  • Topic Author
  • Offline
  • Junior Member
  • Junior Member
More
12 Mar 2019 02:20 #27757 by overdrive138
i have code 0171 and 0172 dtc's rich and lean at the same time
please help thx

Please Log in or Create an account to join the conversation.

More
12 Mar 2019 06:41 - 12 Mar 2019 06:44 #27760 by Andy.MacFadyen
The conditions when these faults were logged may give you a clue --- particularly RPM and throttle opening also coolant temperature.

Then look at live data particularly short and long term fuel trims and O2 sensor output voltage at idle and about 3,000 rpm.


Also are there any splits or leaks anywhere in the air intake ? ---- anything non-standard about the airfilter

" Welcome to the 21st"


Last edit: 12 Mar 2019 06:44 by Andy.MacFadyen.

Please Log in or Create an account to join the conversation.

  • overdrive138
  • Topic Author
  • Offline
  • Junior Member
  • Junior Member
More
12 Mar 2019 10:31 #27763 by overdrive138
Hey andy , everything in the car is stock . I do notice that this car has a plastic intake manifold. I also noticed that if i rev the engine it starts to stutter around 4k rpm or more almost as if i had a rev limiter.

Please Log in or Create an account to join the conversation.

  • overdrive138
  • Topic Author
  • Offline
  • Junior Member
  • Junior Member
More
12 Mar 2019 10:50 #27764 by overdrive138
I also had another code 0137 which i have fixed with replacing bank 1 sensor 2 with a new 02.before that was fixed the car ran horrible smoke out the tail pipe etc. Unfortunately i dont currently own a scanner with live date. I Also did some temp reading on the cat and had a 50 to 100deg difference from front to back could that have anything to do with this? Thx

Please Log in or Create an account to join the conversation.

More
13 Mar 2019 20:06 #27790 by guafa
Hi overdrive,

0137(low voltage) shorted to ground?
0171(lean) shorted to ground?
0172(rich) shorted to voltage?

You should check o2 sensor wires and voltage reference from PCM signal line.

I wouldn't discard 0137 as fixed.

Please Log in or Create an account to join the conversation.

More
14 Mar 2019 00:11 #27796 by wacoeagle
a stuck open t stat can cause crazy intermittent rich issues, if the coolant temp sensor thinks its cold. u may have 2 different problems, like exhaust leak before lambda or A/F sensor.

Please Log in or Create an account to join the conversation.

  • overdrive138
  • Topic Author
  • Offline
  • Junior Member
  • Junior Member
More
14 Mar 2019 16:24 #27817 by overdrive138
i will definitely be checking the t stat thx guys

Please Log in or Create an account to join the conversation.

More
15 Mar 2019 09:17 #27834 by kostelectronics
Check also for correct fuel pressure.

Please Log in or Create an account to join the conversation.

More
15 Mar 2019 16:52 #27854 by Andy.MacFadyen
The possibility of a fuel flow issue can also be added to the list but without live data there is no way to reduce the list of possible causes. A 10 Dollar Bluetooth dongle and an Android app will give you very useable live data

" Welcome to the 21st"


Please Log in or Create an account to join the conversation.

  • cheryl hartkorn
  • Offline
  • Platinum Member
  • Platinum Member
More
15 Mar 2019 20:25 #27860 by cheryl hartkorn
check for a restricted converter. ive seen it on v type engines with a clogged cat itll have rich/lean codes at the same time
The following user(s) said Thank You: Andy.MacFadyen

Please Log in or Create an account to join the conversation.

More
17 Mar 2019 10:08 #27884 by juergen.scholl
Codes for rich & lean mixtures may be caused by evap/purge solenoid issues as well.

freeze frame and live data will b of help.

An expert is someone who knows each time more on each time less, until he finally knows absolutely everything about absolutely nothing.
The following user(s) said Thank You: Andy.MacFadyen

Please Log in or Create an account to join the conversation.

  • overdrive138
  • Topic Author
  • Offline
  • Junior Member
  • Junior Member
More
18 Mar 2019 12:27 #27905 by overdrive138
I just bought a used verus that ill be getting on weds to run live data etc. From my understanding the code is for bank 1 so i will be checking stft and o2 to see if both banks have the issue . i would assume if it was fuel pressure the code would likely be on both banks

Please Log in or Create an account to join the conversation.

  • overdrive138
  • Topic Author
  • Offline
  • Junior Member
  • Junior Member
More
18 Mar 2019 12:31 #27906 by overdrive138
i checked converter temps and front to back temps were different . i dont have a exhaust pressure gauge so I dont wanna change it just yet . i would rather check pressure to be sure as I dont feel the temp test is as accurate.

Please Log in or Create an account to join the conversation.

  • cheryl hartkorn
  • Offline
  • Platinum Member
  • Platinum Member
More
19 Mar 2019 17:33 #27924 by cheryl hartkorn
well keep us updated

Please Log in or Create an account to join the conversation.

More
21 Mar 2019 09:27 #27975 by Andy.MacFadyen
I find temperature tests on converters can be misleading particularly where there is a pipe bend either just before or just after the pipe. Comparing the pre-cat and post-cat O2 is more reliable. The other test than can tell you if the cat is shattered from a misfire is just thump it with the side of your fist. If it rattles it is a dead cat.

" Welcome to the 21st"


Please Log in or Create an account to join the conversation.

  • overdrive138
  • Topic Author
  • Offline
  • Junior Member
  • Junior Member
More
23 Mar 2019 15:04 #28043 by overdrive138
changed the bank 1 upstream o2 sensor and that fixed the issue rich lean code . my verus just got here so now onto some idle diagnosing. car currently has no codes but the idle is still a little rough more so when its cold, but after it warms up it seems to run better . Also I have a noticeable rpm drop stumble right after snap throttle or hold it at 2k for awhile almost like it wants to die.

Please Log in or Create an account to join the conversation.

  • overdrive138
  • Topic Author
  • Offline
  • Junior Member
  • Junior Member
More
23 Mar 2019 15:06 #28044 by overdrive138
when u say compare pre and postcat o2 what exactly am i comparing? thx

Please Log in or Create an account to join the conversation.

  • Not Allowed: to create new topic.
  • Not Allowed: to reply.
  • Not Allowed: to add attachements.
  • Not Allowed: to edit your message.
Time to create page: 0.829 seconds