Results 1 to 4 of 4

Thread: Throwing 2 codes: P1421 & P1423

  1. #1
    Join Date
    Oct 2006
    Location
    Charlotte
    Posts
    4,860
    My Cars
    '97 Estoril M3 Turbo

    Throwing 2 codes: P1421 & P1423

    My M roady just showed two codes: P1421 and P1423

    First code was for the secondary air pump and the second code was a possible fuel or vacuum leak. These could be wrong since they do not have specific bmw software but will someone look up these codes and tell me what they are for.

    When I started the car it was really rough, then ran fine after about 20 seconds. I know the air pump works really only on startup. I just changed it with my unit from my M3 because the original unit bit the dust. It ran fine for well over a month with no issues. What is the deal? Any Ideas?
    | 1997 Estoril M3 - TURBO - |
    | GT35R | 8.5:1 forged internals | ARP stuffs | SS Oring Block w/ elring | Fully balanced & blueprinted 3.3L S52 | Nick G Tuning |
    | 46mm Precision gate| 62# injectors | Dual Walbro's |
    Goal: 600+ whp pump gas reliable 10 second car.
    -2007 335i Sport Package

  2. #2
    Join Date
    Sep 2008
    Location
    Havertown, PA
    Posts
    4,106
    My Cars
    02 e367, 08 Acura TL-S
    1421 is bank 1 & 1423 is bank 2. If the pump has been replaced, look at the check valve and ensure it's clear.

    There's also a bunch of other suggestions on in this old thread:

    http://forums.bimmerforums.com/forum.../t-510853.html

  3. #3
    Join Date
    Oct 2006
    Location
    Charlotte
    Posts
    4,860
    My Cars
    '97 Estoril M3 Turbo
    great. thanks!
    | 1997 Estoril M3 - TURBO - |
    | GT35R | 8.5:1 forged internals | ARP stuffs | SS Oring Block w/ elring | Fully balanced & blueprinted 3.3L S52 | Nick G Tuning |
    | 46mm Precision gate| 62# injectors | Dual Walbro's |
    Goal: 600+ whp pump gas reliable 10 second car.
    -2007 335i Sport Package

  4. #4
    Join Date
    Jun 2008
    Location
    Sunny CA
    Posts
    159
    My Cars
    99 Z3 Coupe
    Old thread about a common issue didn't warrant a new one..
    I was throwing both codes, erased them & they re-appeared. After reading and searching on the web, I headed out to the driveway to see how hard it would be to remove the diverter valve for a vacuum check.

    Never had to. The vacuum hose from that valve was cracked (ok, holey) and a two buck replacement was all I needed.

    God, I love it when there's a cheap fix!

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •