DodgeIntrepid.Net Forums banner

1 - 20 of 22 Posts

·
Woober Goobers!
Joined
·
50,448 Posts
Where are you getting these DTC descriptions from?

DTC=Diagnostic Trouble Code.
 

·
Premium Member
Joined
·
16,955 Posts
Descriptions in FSM are "A rich air/fuel mixture has been indicated by an abnormally lean correction factor" passenger side (P0172) and driver's side (P0175).

I've never had these codes on my Intrepid because I've never owned an Intrepid, but I've also never seen them on my Concordes. :). I've seen some threads where it resulted from the timing belt having slipped. Not saying that's the problem, but a possible cause.

Which engine do you have?
 

·
Registered
Joined
·
11 Posts
Discussion Starter #5
My engine is the 2.7L,no timing belt but a timing chain. Thanks for answering,very appreciated.
 

·
Premium Member
Joined
·
16,955 Posts
OK - that's why I asked. Much more likely to have a tooth or two slip with a timing belt, though I guess it's possible to have a chain jump only one tooth or two without subsequent total failure.
 

·
Registered
Joined
·
277 Posts
SYMPTOM P0172-FUEL SYSTEM 1/1 RICH
WHEN MONITORED
With the engine running in closed loop mode, the ambient/battery temperature above 20 deg. F and altitude below 8500 ft .
SET CONDITION
If the PCM multiplies short term compensation by long term adaptive and a purge fuel multiplier and the result is below a certain value for 30 seconds over trips, a freeze frame is stored, the MIL illuminates and a trouble code is stored.
POSSIBLE CAUSES
•Intermittent condition
•O2 sensor heater operation
•O2 sensor
•EVAP purge solenoid operation
•O2 sensor signal circuit
•O2 sensor return circuit
•Throttle position sensor voltage greater than 0.92 volts with throttle closed
•TP sensor sweep
•MAP sensor operation
•ECT sensor operation
•Engine mechanical problem
•Fuel filter/pressure regulator (high)
•PCM
P0175 same except Bank 2/1
Both Bank O2 Sensors are seeing a rich condition.

First thing I would check is the Air Cleaner
 

·
Registered
Joined
·
11 Posts
Discussion Starter #8
Thank you for posting. I wanted to know if theses DTC were happening often on intrepids.
 

·
Premium Member
Joined
·
16,955 Posts
Coincidentally, my '99 2.7 Concorde just threw P0172 this week for the first time ever. It has 260+k miles on it and all 4 O2 sensors are the originals. I'm probably going to assume that it's the O2 sensor needing to be replaced on mine, but will check out some things in the list that Bob posted - if nothing specific is found, will probably replace both upstreams (since they are the ones that affect tuning).

p.s. - I just checked the air filter - I thought I had replaced it in the last 6 months, and it is in fact almost brand-new clean (car gets driven less than 2000 miles a year now with my 1.4 miles x 2 daily commute). So that's not the problem. I would think most of the other possibilities - i.e., TPS or MAP sensor issues - would be throwing additional codes if they were the problem.

Going to reset the codes and if it comes back, will replace the upstream sensors.
 

·
Premium Member
Joined
·
16,955 Posts
FWIW, the P0172 has not returned. Yay!
 

·
Premium Member
Joined
·
16,955 Posts
All I did was clear the codes. I was out of town all last week and only went to work 2 days of Thanksgiving week, so it hasn't been thru a whole lot of warmup/cooldown cycles yet, so still have my fingers crossed. Not sure what the criteria (i.e., how many out-of-spec instances over how many driving cycles or whatever) it needs to see before it sets a code, so fingers still crossed.
 

·
Premium Member
Joined
·
16,955 Posts
Coincidentally, my '99 2.7 Concorde just threw P0172 this week for the first time ever...Going to reset the codes and if it comes back, will replace the upstream sensors.
FWIW, the P0172 has not returned. Yay!
This is too weird. That first post of mine was Nov. 22, 2014. Yesterday, Nov. 21 2015, the P0172 returned. Going to reset it and see if that takes care of it. I wonder what would make this happen once each year this time - temperature fluctuations, or transition to winter fuel? (It's the same '99 2.7 engine that I transplanted to the '98 body this past summer. Using the '98 3.2 PCM now.)
 

·
Registered
Joined
·
6,836 Posts
Peva, I think the 2.7s do run just a little bit rich when paired with a 3.2 ECM. I don't have any scientific way to prove my thought, but I have noticed that my 2.7 is getting about the same gas mileage as my 3.5 but has much snappier throttle response and a slight amount of grayish smoke from the exhaust regardless of outside temp.
 

·
Premium Member
Joined
·
16,955 Posts
Peva, I think the 2.7s do run just a little bit rich when paired with a 3.2 ECM. I don't have any scientific way to prove my thought, but I have noticed that my 2.7 is getting about the same gas mileage as my 3.5 but has much snappier throttle response and a slight amount of grayish smoke from the exhaust regardless of outside temp.
The 3.2 PCM may have something to do with it. I will say that last year when this code was thrown, it was with all factory 2.7 setup. I just found it awfully coincidental that the code is thrown once each year at the same time.

I'm sure hopeful it will not return (at least until this time next year) - I reset the code this afternoon, so we'll see. I also put a can of Sea Foam in a full tank of fuel this afternoon too in case it's a fuel injector gunk issue. The air filter was clean last year when the code occurred, and I replaced it this summer when the engine was swapped over (less than 1000 miles ago). Checked spark plugs at engine swap - looked close to new (I don't keep written records on it anymore) - been putting less than 5kmiles on it a year for the last 5 years. I would expect that if an ignition coil (or plug) was a problem, there'd be some mis-fire codes, but I also know that the codes don't always follow logic.

Anyway, not a big deal at this point. May throw a new set of plugs in if the code returns anytime soon.

I don't expect this engine to do any better on fuel mileage than my 3.2. My 3.2 always got better than 30.5 on the highway according to the OTIS - sometimes as high as 32+ on a long trip loaded with people and luggage, which I thought was amazing (assuming the OTIS is correct). Won't really know for sure as this car is now my daily driver 1.4 miles x 2 commute engine - no long trips.

Your slightly grey smoke you think is fuel, not oil (valve stem seals)? Oil would be more bluish?
 

·
Premium Member
Joined
·
16,955 Posts
This is too weird. That first post of mine was Nov. 22, 2014. Yesterday, Nov. 21 2015, the P0172 returned. Going to reset it and see if that takes care of it. I wonder what would make this happen once each year this time - temperature fluctuations, or transition to winter fuel? (It's the same '99 2.7 engine that I transplanted to the '98 body this past summer. Using the '98 3.2 PCM now.)
FWIW (probably not much), this code has not returned on mine since resetting it a few weeks ago. Will look for it at the same time next year. :)
 

·
Registered
Joined
·
277 Posts
Odds are that the O2's are a little slow and lazy due to age. Can not react quick enough as the seasonal change in air density. Reset likely allows the Long Term and Short Term fuel trims catch up and hold the mixture close enough for the year.
 

·
Premium Member
Joined
·
16,955 Posts
Hello Bob!

Makes sense. Thanks.
 
1 - 20 of 22 Posts
Top