03 truck, PO300 and Liscense problems

[PladdPezzPunk]

So was tuning a truck today and was actually having two problems. first is after i got things where i wanted them, i keep getting a po300 misfire code. the truck dosn't appear to be skipping however the code keeps popping on.

second problem is i now can't reflash the truck without using another liscense. Even though i've flashed the truck 4 times today, it now keeps asking me to liscense the pcm again.

cann anyone help me with these two issues as i'm stuck. the 300 i should be able to figure out once i clear my head but any thoughts would be great, the liscense issue is going to cost me and i am lost as to what i can be done about that

I have attached the stock tune before any tuning was done, the tune that is in the truck right now, and the last calibration that i flashed to the truck.

thanks in advance for the help as it is much appriciated.

[Blacky]

P0300 requires you to perform a CASE (Crank Angle Sensor) learn. A CASE learn is required if you change PCMs or change anything mechanically that effects the relationship between the crank and the crank sensor.

The license issue is due to the PCM's serial number being deleted which required EFILive to insert a new serial number into the PCM. You should also put your VIN back into the PCM. You can use the Scan Tool to enter a new VIN.

The serial number can be deleted by GM's programming system used by GM dealers or by an old version of EFILive during a full reflash. If you have only used EFILive, please make sure you update your software to the latest version, to prevent a repeat occurence:
http://www.efilive.com/download.aspx

Send me an email paul@efilive.com with the following info:
Your FlashScan serial number and auth code, as per this thread:
http://forum.efilive.com/showthread.php?t=5790
And we'll replace the used license.

Regards
Paul

[PladdPezzPunk]

thanks for the help paul. Now I'm still just a little confused but to clarify, what did i change to make the serial number to the pcm change?

Also, on the po300. i did the case relearn and still was getting the code. any other thoughts.

[joecar]

Is there any chance you're idling lean...?

[PladdPezzPunk]

Is there any chance you're idling lean...?

actually i had it running too rich origionally at idle, leaned it out a bit and it is running great but still the misfire code.

also watched some scan data on the snap on solus and saw that there are repeated misfires in all cylinders at idle. i have the freeze frame data and it appears to only happen at idle. every other rpm range is fine. I'm still kind of scratching my head. i think this weekend, i'm going to clean the MAF and throttle body as there is alot of carbon build up and see if that will straighten out some of it.

[joecar]

If it was idling too rich for a period of time, then the plugs may be carbon fouled which will cause misfires.

Dirty MAF will cause airflow/airmass to read low causing PCM to use more ignition advance which may show up as knock; cleaning the MAF periodically is a good idea.

[Blacky]

thanks for the help paul. Now I'm still just a little confused but to clarify, what did i change to make the serial number to the pcm change?

There is nothing you did to cause the problem. It is a problem in the firmware in the PCM.
The data (serial number, VIN and other similar data) is stored in an area of the PCM that must be erased during a full-flash programming session. EFILive attempts to save the original data from that area of the PCM's memory so that it can be restored during the full-flash process. Sometimes it is not restored correctly. We are working on changes to the EFLive software to try and work around the problem.
Just for you info, GM's own service programming system also suffers from the same problem.

Regards
Paul

[Blacky]

Also, on the po300. i did the case relearn and still was getting the code. any other thoughts.

It could just be that you have a cam profile that "looks like" a misfire to the PCM. The PCM is measuring the time differences (acceleration) of the crank shaft and comparing it to the reference data saved during the CASE learn procedure. If the cam is choppy or has a particular lope at idle, it can cause the PCM to incorrectly detect a misfire at idle.

I believe there is a calibration to control the lower RPM limit for the misifre test. Just set that value to something higher than the lowest RPM where you are seeing false misfires.

But you should make sure the misfires are not real misfires before changing the lower RPM limit.

Regards
Paul