News

355 P1451 5.2

Discussion in '348/355' started by Beetle, Sep 21, 2020.

  1. Beetle

    Beetle Formula Junior
    Silver Subscribed

    Apr 10, 2013
    757
    Victoria
    Full Name:
    Paul, Australia
    Hello all
    Question. Can or is it possible if you have code P1451 short to ground Secondary air motor. Could that create or give P0133? O2 Slow to react
    TIA
     
  2. To remove this ad click here.

  3. Qavion

    Qavion F1 Rookie
    Silver Subscribed

    Feb 20, 2015
    4,887
    Sydney
    Full Name:
    Ian Riddell
    Electrically, not likely (unless the engine harness is damaged and the wiring for those two is rubbing together). The circuits have separate fuses and no common wiring (other than the battery itself).

    I think I read somewhere recently that adding extra air helps to heat up the cats faster. If the pump is broken, could this cause the slow to react message? If so, then why aren't both O2 sensors showing "slow to react".

    Is the air pump completely dead? Could it be not putting out sufficient air for both sides (and the check valve on only one side is opening or one O2 sensor is slightly more sensitive than the other side)?

    Experts?
     
  4. Beetle

    Beetle Formula Junior
    Silver Subscribed

    Apr 10, 2013
    757
    Victoria
    Full Name:
    Paul, Australia
    Definitely only 1 02 sensor. I didn't hear the secondary pump running that's why I asked this question mate. I believe the air pump is cactus. Going to pull it and check it out. I heard the same comment about it helping heat the cats up also.
     
  5. Qavion

    Qavion F1 Rookie
    Silver Subscribed

    Feb 20, 2015
    4,887
    Sydney
    Full Name:
    Ian Riddell
    I can't figure out how the Motronics ECU is detecting a short to ground on the pump. The only interface between the ECU and the pump is the relay in the footwell. I would check the relay first. Clear the codes, then interchange or replace relay "L"(air pump). Relay "F" (side and tail lights) has the same part number.

    While you're there, check the fuse (31) and check the fuseholder for signs of melting.
     
  6. Beetle

    Beetle Formula Junior
    Silver Subscribed

    Apr 10, 2013
    757
    Victoria
    Full Name:
    Paul, Australia
    That whole relay panel, relays and fuses is brand new wouldn't have done 4hrs driving mate but yep I will check
     
  7. To remove this ad click here.

  8. Beetle

    Beetle Formula Junior
    Silver Subscribed

    Apr 10, 2013
    757
    Victoria
    Full Name:
    Paul, Australia
    Secondary air pump out. It works just fine. No bearing noise or anything out of order. I cleaned the air filter for it. Think I will clean the MAF Check fuse, relay and drive. Could be just one of those little things!!!
     

Share This Page