code 42 & 43 help
Thread Starter
Teching In
Joined: May 2012
Posts: 48
Likes: 2
code 42 & 43 help i just got done with a lt1 swap into an old square body chevy truck. the engine is a 94 f body i think. the guy didnt know what it was out of. i dont know if it ran good or not before he brought me the engine. the harness was already butchered so i got one from picknpull out of a 95 caprice and now i have these 2 codes and it runs and idles fine but backfires out the intake when you rev it. i know the f body only has 1 knock sensor and the caprice i got the harness from had 2. so i got another knock sensor and hooked evertything up. i even flashed it to a 95 caprice file and it didnt change. flashed it back to what the pcm origianlly was and unplugged one knock sensor and same thing. i cant tell if i have a problem with the tuning or its an actual problem with knock sensors, ign module, knock sensor module(?)... it has brand new distributor, plugs & wires, 02s, knock sensors. im more familiar with ls stuff so i hope someone has a better idea of what i need to do. help please
TECH Fanatic
Joined: Sep 2010
Posts: 1,037
Likes: 2
42 is EST Grounded.
43 is ESC fail.
http://www.camaroz28.com/forums/lt1-...-check-648267/
http://www.ls1lt1.com/forum/lt1-|-lt...c-failure.html
43 is ESC fail.
http://www.camaroz28.com/forums/lt1-...-check-648267/
http://www.ls1lt1.com/forum/lt1-|-lt...c-failure.html
Thread Starter
Teching In
Joined: May 2012
Posts: 48
Likes: 2
Ok I'll double check the knock sensor wires for short/ground and if it has 5v. If its good. Then what throw a knock sensor module at it?
I found a write up about the EST grounded but can't find the "EST" circuit in the wiring diagrams. Is it just the one wire from the PCM to the ICM. B5 circuit 423? That wire is good into harness...throw a ICM at it?
I found a write up about the EST grounded but can't find the "EST" circuit in the wiring diagrams. Is it just the one wire from the PCM to the ICM. B5 circuit 423? That wire is good into harness...throw a ICM at it?
Thread Starter
Teching In
Joined: May 2012
Posts: 48
Likes: 2
put another pcm and ignition module on it and got rid of the code 42 but still has 43 for the knock sensors. i tried a few different knock sensor modules and nothing changed it. still backfires thru the intake.
has no one else on here had this problem?
has no one else on here had this problem?
