News

Code P0491 & P0492 - Secondary Air Injection

Discussion in '612/599' started by Vito, Apr 3, 2017.

  1. Vito

    Vito Formula Junior
    Silver Subscribed

    Apr 29, 2004
    336
    Dutchess County, NY
    Full Name:
    Mark
    A recently acquired 2008 599 displayed an engine control system (ECS) error and the OBD codes revealed P0491 and P0492, Secondary Air Injection issue. The car had been started from cold the other day having sat for about a week since the last running. After a moment of warm up time and about a mile of driving, the check engine light cam on with the Engine Control System Failure (ECS) warning. The motor ran fine, no issues there. I've seen in other threads here that these codes have appeared in 8 cylinder models but I was unable to find a similar thread for the 12 cylinder cars. Has anyone else experienced this same ECS code? If so, what was done to resolve the problem? I've had no further issues since simply clearing the error codes. Thank you for your comments.
     
  2. DXB599

    DXB599 Formula Junior
    Silver Subscribed

    May 31, 2015
    254
    Dubai
    I'm curious about this as well as I've had the same issue with my 2010. I clear the codes via the battery disconnect in the trunk, but after driving for 20-30 minutes the ECS comes back on. Car runs perfect. Next time I bring it in for annual service, will have them have a look as it's annoying to see the light on.
     
  3. Motob

    Motob Formula 3
    Professional Ferrari Technician

    Nov 11, 2003
    1,879
    Berkeley, CA
    Full Name:
    Brian Brown
    P0491 and P0492 indicate that you have insufficient air injection flow into the exhaust manifolds. The oxygen sensors are looking for a leaner mixture caused by the air being injected into the exhaust and are not seeing it and setting the codes. The fact that it is the same code set on both sides indicates that it is a problem common to both sides.
    There is a vacuum solenoid valve that provides manifold vacuum to the air injection valves for each side of the engine. You either have a blockage in the vacuum system or a leak in the vacuum system causing the valves to not open. Further diagnosis is required.
     
    Skidkid likes this.
  4. DXB599

    DXB599 Formula Junior
    Silver Subscribed

    May 31, 2015
    254
    Dubai
    Many thanks for the detailed response. Quite helpful.
     
  5. Vito

    Vito Formula Junior
    Silver Subscribed

    Apr 29, 2004
    336
    Dutchess County, NY
    Full Name:
    Mark
    Thank you for the information. I'll share this with the technicians.
     
  6. Vito

    Vito Formula Junior
    Silver Subscribed

    Apr 29, 2004
    336
    Dutchess County, NY
    Full Name:
    Mark
    I've cleared the error code, restarted the car (it was not totally cold though) and drove about 20 miles without the error reappearing. Could it have been a one time glitch?
     
  7. vjd3

    vjd3 Formula 3
    Rossa Subscribed Owner

    Jun 3, 2005
    1,296
    Massachusetts
    Full Name:
    Vic
    Those secondary air injection pumps run for just a couple of minutes on cold start to reduce emissions, with no effect at all on how the engine runs. The only downside to a problem is the check engine light and that you will likely fail emissions. The Porsche 993 suffered from clogged secondary air injection ports in the heads from carbon and it was a bear to clean them out. This sounds like it would be a more straightforward issue but it is more of a nuisance than a running problem.

    You can reset the check engine light but it is likely to reappear once the OBD2 system runs all its diagnostic checks and flags it. This can take a lot of driving cycles to occur. With the 993 you could reset the code, and then race against the computer to get the car inspected before it threw the check engine light and failed, because the car ran fine otherwise.
     
    montegoblue likes this.
  8. Vito

    Vito Formula Junior
    Silver Subscribed

    Apr 29, 2004
    336
    Dutchess County, NY
    Full Name:
    Mark
    Car restarted & driven several time since codes cleared, longest drive was two 65 mile routes, codes have not reappeared.
     
  9. francars

    francars Karting

    Nov 28, 2006
    109
    Bay Area, CA
    Full Name:
    Francisco
    While driving to get annual service on mine the CEL came up. Turns out the Secondary Air Pump is faulty and needs replacement. Oh well...
     
  10. Motob

    Motob Formula 3
    Professional Ferrari Technician

    Nov 11, 2003
    1,879
    Berkeley, CA
    Full Name:
    Brian Brown
    I would keep driving the car to see if the codes come back. It doesn't hurt anything if they do. It may have been a one time occurrence, caused by a partially blocked vacuum hose or the air injection pump had an intermittent failure.
     
  11. vincep99

    vincep99 Formula 3
    Silver Subscribed Owner

    Jun 8, 2009
    1,631
    I have the same problem in my 2011 458. Comes on maybe twice a year. I just checked all the hoses and connections, could not find anything.

    I noticed I can clear the temporary code but a permanent code remains.

    I am going to keep looking.
     
  12. PRO SYSTEMS

    PRO SYSTEMS Rookie

    Mar 4, 2017
    35
    Windermere, FL
    vincep99, Did you ever resolve your issue with your 458?
     
  13. Jasflora

    Jasflora Rookie

    Sep 30, 2018
    37
    Full Name:
    Jas flora
    I am getting
    the same on my 2011 458 Power seems a little diminished though this may be my paranoia. I'm going to get the Ferrari tech take a look at it this week
     
  14. rob5819

    rob5819 Rookie

    Dec 12, 2017
    24
    San Diego
    Full Name:
    Rob Barry
    Just got this error code on my 2014 458 Spider: P0491 AIR System Insufficient Flow Bank 1." First time driving it in about four weeks because of weather. Have an appointment with the dealer next week to investigate. Will update thread with any relevant information.
     
  15. rob5819

    rob5819 Rookie

    Dec 12, 2017
    24
    San Diego
    Full Name:
    Rob Barry
    Took my 458 in today for the above problem and the error code was gone when we turned the car on at the dealer. They are going to take a closer look over the next few days, plus I just got the recall notice for my secondary air bag and I am hoping they can get that taken care of as well. Hope to know more on Monday.

    Did anyone else have the code clear after a few engine starts?

    Rob
     

Share This Page