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Error Code: P0302/P3191

Discussion in 'Gen 3 Prius Main Forum' started by kdyj15, Sep 29, 2015.

  1. kdyj15

    kdyj15 Junior Member

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    I leave my car for 2 weeks without driving, and when I start the power, I have check engine light on and I drive to the dealer right away. Mechanic performs diagnostic test for engine misfire no engine miss found. The error code is P0302/P3191. The mechanic told me that I always run the car in very low on fuel, and it causes the 2nd cylinder misfile or not running when the fuel is very low. They suggest me always pump the gas when the fuel indicator has 2 bars left.

    My question is that: How come the car cannot run in low fuel, low fuel doesn't mean no fuel, and it can damage the engine/cylinder?

    Any one has same experience? My car is 3 months old and already 5500 miles, and every tank I can run about 500-530 miles.
     
  2. HaroldW

    HaroldW Active Member

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    There is a problem of some sort that is triggering this code. More than likely a low voltage 12v battery because it sat without running for two weeks? You more than likely have the intake manifold issue that many Prius cars have? I would take it to another dealer because I think you got a pretty lame excuse for the codes? H
     
  3. HaroldW

    HaroldW Active Member

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    I run my tank down to no pips around my area all the time without issue going after my 1000 kilometer tanks. Running low on fuel has no baring on anything. It has fuel or it doesn't. H
     
  4. bisco

    bisco cookie crumbler

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    unless there is contamination in the bottom of the tank. was the mech right about you running on low fuel all the time?

    agree with harold on the 12v, you should have it tested, to make sure it isn't a problem.

    maybe starting up after 2 weeks stirred up the bottom of the tank.
     
  5. m.wynn

    m.wynn Senior Member

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  6. kdyj15

    kdyj15 Junior Member

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    Thank you HaroldW
    How do I tell mechanic that I have "intake manifold" issue, and how should I describe the issue to him? When I start the engine first time after 2 weeks, I can hear the engine sounds weird, but after drive a while, and everything come to normal. Two days after I drive and after mechanic reset the engine light, I do not have any issue and does not hear any weird sound from engine. Do I still need to go check my engine?

    Suggestion??

    kdyj15
     
  7. bisco

    bisco cookie crumbler

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    the 'intake manifold issue' is from starting a car that had previously been shut down before completing the warm up cycle. it is a one off and not a regular issue. there is no fix.

    why don't you pump the gas and check the 12 volt health instead of looking for some obscure cause?
     
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  8. HaroldW

    HaroldW Active Member

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    Kdyj15 Bisco pretty well covered this issue. I personally have herd this weird sound when starting my 2014 prius a couple times. I don't think it something to be concerned with. Have your 12v checked. You want to see 12.6v after sitting over night. If you see 12.1 v your battery is week. You can check this with a multi meter. The 12v does not power the starter in your prius but it does control the PC's and that is why funny things happen when the 12v is weak. H
     
    bisco likes this.
  9. Blondetwinster

    Blondetwinster New Member

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    Yesterday my check engine light came on and the code was P0302. I had been low on gas and the previous 2 days it did rattle for a few seconds upon starting and idle rough then start like normal. Then yesterday the light came on so I got the code checked and called to get an appointment today (with the dealership which I hate but the only one available without waiting 2 weeks). As everything I've read says not to drive with a cylinder 2 misfire I wanted to check immediately. I know there are basic tests you can do yourself such as switching the coil and/or spark plug to a different cylinder to see if it throws a different code but don't have the appropriate tools to do so.

    I explained all this to the dealership and they claimed they checked everything and needed to reflash the ECU system as that was causing it all. From what I have googled it does not seem related but perhaps I don't know enough about it. They said they changed my spark plugs 57,000 miles ago so they were "fine". When I get my report from the inspection they marked Fluid Leaks (engine/transmission/differential) and Exhaust System (damage/leaks/corrosion) as Needs Immediate Attention and yet claimed my car was good to go.

    So I'm concerned that perhaps the issue is not actually diagnosed OR fixed. I do have to drive to and from work (30 min each way) the next 5 days before getting another appt. I don't have any other ride options and I have been following this forum for awhile and thought I'd put some feelers out on those that know more about Prius' than I do on whether their fix with the ECU reflash is legit or if I need to take it somewhere else.

    On the paperwork they gave me it says this exactly: Inspected and found codes P0302, C2122, C2121, P0A0F, P3191, P0302, C2175. Rec reflash per TSB. I did google all the codes and some seem to have more to do with the sensors in the tires but also some just generally listing "engine does not start".

    Any help or advice is much appreciated! I did put some cardboard under my car after I parked it once I read the fluid leak check box just to see if anything leaks under the car.

    Thanks!