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Discussion Starter · #1 ·
I have NO check engine Light but I do have a CODE 42.
When I first got the car fired up after installing the new motor, I had a Check engine light for Code 42 It end up being a broken wire I fixed it the check engine light went away the car ran great.
I drove it around for 10 to 20 miles then it started to run BAD missing stalling something was amiss.
Now No Check engine light but I now have code 42 again.
Any Ideas I don’t think it the same wire again could be an Ignition Mod Or what.
The car idles Ok but not the best it ides ok then starts acting up missing and cutting out but not idling.
Driving from a stop not a lot power after 1500 to 2000 RPM’s the power go’s flat like it’s not advancing the timing.
The motor has 340+ H/P and 427Tq It should be able to smoke the tire when you stand on it from a stop It will not.
 

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I do have a CODE 42.
CODE 42

Trouble Code 42 indicates that there may be a malfunction in the Electronic Spark Timing (EST) system.

During cranking, the timing is controlled by the ignition module while the ECM monitors the engine speed. When the engine speed exceeds 400 RPM, the ECM sends a BYPASS signal to the ignition module which switches the timing to ECM control. The ECM calculates what the timing should be then "tells" the ignition module via the EST circuit.

An open or ground in the EST circuit will stall the engine and set a Code 42. The engine can be re-started but it will run on ignition module timing.

The conditions for setting this code are:

* System in BYPASS mode but the ignition module is still controlling timing

- or -

* Engine speed > 600 RPM with no EST pulses (ECM controlled timing) going to the ignition module for 200 msec.


Typical causes for this code include:

1) BYPASS line is open or grounded
2) EST line is open or grounded
3) PROM or CALPACK not seated properly in the ECM
4) Poor connections between ignition module and ECM
5) Poor routing of EST harness and/or poor quality ignition wires (EMI induced electrical noise)
6) Faulty or incorrect ignition module
7) Faulty ECM
 

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Discussion Starter · #3 ·
Found it.

The left rear intake runner gasket at the intake base gasket must of shifted last time installed it.

It ran good for a while I guess it let go. it was not centered on the runner.

So I fixed the code 42 new Ignition Mod .
Found why it ran ruff bad gasket.
I ordeed one I sould get by the end of the week.
 
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