Just did a timing belt/starter/valve cover update on my 2004. Started it up, everything was fine.
Started it up 15 minutes later, let it idle for 10 minutes and it started running very rough — OBD gave me these codes:
Couldn’t believe I blew 4 coils - I pulled of #1 and swapped it with into my 1998 LC. Immediately it tripped the engine light and codes:
P1300
P0301
P0302.
Meanwhile the coil from the 1998 in the 2004 - that truck started and idled perfectly — checked codes and all clear.
I put a spare new coil into 1998, and back to normal.
So one bad coil ended up blowing 7 different codes (on 2 trucks). I was fortunate to pull the bad coil first.
OBD is definitely helpful, but ‘exact science’ it is not. Will generally point to correct area, but details can be lacking — precision akin to playing darts with a drunk girlfriend.
(Similar mystery tracking down a bad valve with multiple vapor recovery codes last month)
Started it up 15 minutes later, let it idle for 10 minutes and it started running very rough — OBD gave me these codes:
Couldn’t believe I blew 4 coils - I pulled of #1 and swapped it with into my 1998 LC. Immediately it tripped the engine light and codes:
P1300
P0301
P0302.
Meanwhile the coil from the 1998 in the 2004 - that truck started and idled perfectly — checked codes and all clear.
I put a spare new coil into 1998, and back to normal.
So one bad coil ended up blowing 7 different codes (on 2 trucks). I was fortunate to pull the bad coil first.
OBD is definitely helpful, but ‘exact science’ it is not. Will generally point to correct area, but details can be lacking — precision akin to playing darts with a drunk girlfriend.
(Similar mystery tracking down a bad valve with multiple vapor recovery codes last month)
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