If the computer detects 'normal' readings after a number of 'drive cycles', CEL codes can clear themselves.
It seems CA cars have P0421 issues -
http://www.miataforum.com/vb/printth...6&page=1&pp=25
I had a CEL (code P0421) this Sun. After driven a couple of days for about 100 miles. This morning it went away when I start the car. I am under the impression that the CEL has to cleared and does not go away by itself?!
Gab
Gabriel
If the computer detects 'normal' readings after a number of 'drive cycles', CEL codes can clear themselves.
It seems CA cars have P0421 issues -
http://www.miataforum.com/vb/printth...6&page=1&pp=25
Sammm, Thanks! This make me feel better knowing it is not the CEL light burned out! May be my 1st CAT is getting weak and on life support. I just replaced the 1st O2 sensor, therefor, it can't be the O2 sensor. The P0421 code is pretty specific for the 1st CAT. The O2 sensor had a different code. Can't wait to convert it to run on only one CAT.
Gabriel
I just put a piece of black electrical tape over it... goes away every time!
Actually if you ignore it long enough the CEL will eventually burn out and you have a "permanent fix" of ALL your CEL problems!I just put a piece of black electrical tape over it... goes away every time!
Gabriel
'94 Black & Black & Tan
'99 head swap, JR header, TDR intake & header blanket, MegaSquirt, RB hollow bar, Tein Flex, 15x8 6ULs, HD M2 Sport, FM cat, Borla cat-back, black '95M interior, MOMO Zebrano, IL Motorsport console...
Dyno Days
8/16/08 (bone stock): 103.1 hp/99.0 lb-ft - Dynojet
8/23/08 (Borla cat-back): 108.2 hp/104.1 lb-ft - Dynojet
8/13/11 (more stuff...): 126 hp/116 lb-ft - Mustang dyno
Roger Moore: the Danny White of James Bonds
I wonder how many years one would get in the custody of the state if one created... err... um... a "test rig to test inspection machines" that looked just like the OBD-II port and allowed the car to pass.
Daily Driver: 2013 Club edition in Pearl White Mica
Lightness? What's that? I drive a PRHT!
I know a guy that can do the hardware... he doesn't have programming knowledge though...
Daily Driver: 2013 Club edition in Pearl White Mica
Lightness? What's that? I drive a PRHT!
P0421 is a very common code in Miatas and others........my 99 Miata set that code real regular, a new 02 sensor cut the frequencyand since the new spark plug wires its only come back once. I have a scanner so I would just clear it every time, what used to be 2 or 3 times a week is now maybe once every month or two.