LT1-LT4 Modifications 1993-97 Gen II Small Block V8

Code 43 & 42...Please Help!

Old Mar 10, 2010 | 07:52 PM
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Default Code 43 & 42...Please Help!

Ok guys I need to know if anyone has had these issues..

I did a search and found some old threads on these codes but no real answers on what was the reason or the fix.

Here is a little background on the car...
I put the motor together and it ran great for the first 500 miles or so then it started to sputter at around 5800rpms (had a new opti already) so I assumed I got a bad opti so I replaced it with another new opti and it has the EXACT same prob so I think we can rule the opti out....I know it is not mechanical I checked push rods and springs and all of them are ok....

The SES light is on so I pulled the codes
42 - Ignition control circuit, short or grounded
43 - Knock sensor circuit


I am hopeing someone else has had this prob and knows whats the best plan of action!


Thanks

Matt
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Old Mar 18, 2010 | 02:00 AM
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Hey guys I just wanted to update this in case anyone ever has a similar problem and uses the search they will know how I fixed mine... I Hate it when I do a search and there is a thread about my EXACT problem that no one ever updated when they figured it out!!

Anyways heres what it was


Code 42 - Bad ICM everything else was good... from what I understand now a bad coil will cause this same issue...
Code 43 - The previous owner had cut and spliced into the Knock Wire from the ECU so I ran a new good wire and made sure I had 5volts at the end of it...
However that did not solve my problem....the knock sensor was completely dead...I put a new Knock sensor in and checked the ohms and now my SES light is off
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Old Mar 18, 2010 | 03:01 AM
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Nice find! My car is doing the same thing it did 2 years ago by randomly dying out and now no start at all. Changed the ICM and still nothing, looking at the new opti being junk...
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Old Mar 18, 2010 | 03:09 AM
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Have you checked to coil yet??


Where did you get your opti from??

Matt
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Old Mar 18, 2010 | 05:06 PM
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Haven't checked the coil, but I'm not getting a signal to the ICM. Car was making a funny scratching sound between 2nd and third gear shifts, I think maybe the rotor came off the mounting bracket in Opti...
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Old Mar 18, 2010 | 08:38 PM
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Yea that is a great possibility its pretty common for them tome fall out...I always loc tite them before installing....
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