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Murphy’s Law with my OBD2 reader

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gnuarm:

--- Quote from: RJHayward on December 31, 2022, 08:00:44 pm ---   Yeah, 'Periodic service due' (thanks, jonpaul), can happen, as the critical and recommended issues aren't distinguished, by the single 'Check Engine'.
You might think a major issue like that would not last long, before manufacturers step in and get some kind of system feature, to distinguish things like:
   'wiper fluid low', vs 'engine overheat'.

   Supposed to be an 'open source' spec. you could look up, and get generic info. across many brands, or manufacturers.  It's a matter of customer ease, and transparency, across the various markets.
Some, build obdII in, reluctantly, and worse, presently teaching customers they might, maybe, just ignore the flakey seeming indicator, not a path towards reliability.

--- End quote ---

Clearly the problem is they don't have enough processing power in cars to be able to distinguish the causes of problems.  ;)

In reality, you would think one of the many displays in a car could indicate what is actually wrong.  I believe at this point, it is only the very least expensive models in an automaker's line up that don't have at least a 7 inch display.  I can only think this is about getting you into the car dealer. 

There are the standard codes which are part of the OBD II spec.  But manufacturers also add their own, proprietary codes, which tend to not be so public.  A bit of Internet searching will uncover their meaning.

edy:
My car notified me of Service B a few weeks ago. It eventually showed 5% oil life left, then when it supposedly became 0 it started counting KM negative… look at attached image, with the “wrench sign” showing. Then when my engine light came on it also took out the anti slip traction control option.

I checked my engine oil, it was low, I added more oil a couple weeks ago. My engine does slowly burn oil, it’s very light 0W20 synthetic for Honda CR-V engine. Anyways, everything reset a few days after the engine light went on. I never had a chance to plug in the OBD2 reader (see photos attached still in package).

I’ll plug it in and report on the results.

edy:
Ok, code has been read and I’m trying to make sense of it. Again, please note the sequence of events over last few weeks.

1. Oil life % was lowering and it recently when to 5% then 0, at which point the Service B notice goes on and a little yellow wrench icon displays.

2. I added some oil myself just to keep me going as I also noticed the red oil little flicker once when I was driving. I checked the oil and indeed it was low. My engine does burn through the light 0W20 oil slowly over a few years so I periodically do have to add a bit. There is no obvious leak, I have no spots anywhere on my parking spot that I park consistently on indoors for years.

3. About 1 week ago the MIL engine service light went on. I kept using my car and about 5-6 days later it turned off all by itself. I didn’t do anything at all except lift the hood, make sure I didn’t forget to tighten my oil cap, checked oil, checked gas cap, etc… this is all *before* I even hooked up the OBD2 reader.

4. It’s been a few days now, no MIL light. Car starts and runs fine just like it did before and during the time the MIL light was on. I plugged in my OBD2 reader and have attached the following images:

- initial screen showing status (1 page)
- error code that triggered MIL (1 page)
- snapshot of the condition at time of error (7 pages) - next post as it exceeds 10
- I/M emissions test status since error cleared (3 pages) - next post as it exceeds 10

Based on this data I came upon this info:

https://www.yourmechanic.com/article/p0341-obd-ii-trouble-code-camshaft-position-sensor-circuit-range-performance-by-jay-safford

I am going to assume at this point that it was a temporary glitch and that it won’t happen again. Seems like it is likely a sensor or wiring issue but hopefully unlikely to actually be a mechanical flaw underlying what this sensor is actually looking for. Maybe just something when doing a cold start on a day after a weekend not driving, took a few more cranks to get going, and not so much oil (before I added some more)… If the timing belt, crank shaft position or actual mechanical issue still there it would have retained the MIL and probably caused some noticeable engine problems yet I am driving fine and light went off on it’s own. Any thoughts?

edy:
Here are the other pages I read from the ODB2 device, I believe it’s a snapshot (7 pages) of the engine conditions at time of the code trigger, and 3 pages of what I believe are emissions I/M data since the last error? I guess that tells you what systems were tested and passed? The 1st page of the snapshot is the last attachment even though I added it first.

Here is more info:

https://hondatheotherside.com/p0341-honda-dtc-code/

Note that I *DID NOT* clear any codes or any data whatsoever using my OBD2 device. Everything is still there, I only used it to read stuff. Whatever happened the car did itself, I guess after it did more checks after several driving cycles and figured things were ok again. I believe if you wait long enough even the original error code will erase itself and I won’t be able to read it anymore with my OBD2 reader?

tom66:
May be worth looking at the code set criteria for P0314 and it might give you some ideas.  Also if your car is constantly burning oil have you considered going up a grade?  I don't know what the tolerance of your engine is but remember the oil specified has to be able to start the car without excessive wear at the lowest operating temperature, for instance -25C when the oil viscosity is poor.  If your car never experiences those temperatures due to location or because it's garaged then a thicker oil may be OK and limit the burn rate. 

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