P1138/58 diagnosis - not the obvious cause!

neil30076

Well-known member
Apr 20, 2004
276
0
Cary, NC - ex - San Diego
98 Disco 1, 150k miles.
CEL on all the time with various combinations of 1138/1158 For months I have had a problem with the speedo either not reading at all, or jumping around and sticking at 130+, or sometimes even working, the odometer worked all the time, but decided to try a new VSS anyway.Cruise control dead also. CEL on all the time with various combinations of 1138/1158, OBDII read out says 74kph all the time, showed lean readings on bank 1.

Swapped out VSS, no change.
Pulled the instrument console, everything looked good, screws tight on back of speedo, connector cleaned, no change.
Pulled console again, this time removed speedo from cluster. Cleaned the 4 screws that hold it in with electrical contact cleaner, cleaned the copper strips under the screws, and reassembled.

All problems gone.
Just an idea for anyone chasing similar gremlins.
 

cdansan

Well-known member
Sep 15, 2008
537
0
Northwestern, Vermont
I get P1138 all teh time, I think in my case it is the catalytic converter falling apart.
I get pieces of the catalytic converter stuck in the muffler (Borla) every couple of weeks.
Dan