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Posted 4 minutes ago (edited)
man am I sick of dealing with all sorts of gremins on my 2004 GMC sierra 1500 SLE with 5.3
It all started when I replaced/rebuilt my trans. no problems there..
But I had to have the PCM reprogrammed( blackbear) becasue of the new tranny needed the stock tranmission table put back in.
I had a spare pcm that my tune was revised and loaded and I installed it.

NOTHING BUT ISSUES SINCE.

1) the fan operation was reversed after the PCM install..meaning the small fan and large fan oeration sequence were reversed
2) the TCC occasionaly does not lock up or get called to lock up( verified on scan tool) . so far its been a nuisance
3) the fugger won't ide for squat and sometiems just dies. especially if you whack the trhottle and let off in traffic lets say.. of you get off an highway ext ramp nad pupp up to stop .
it seems it cant find idle spot.

Ive checked all the friggen grounds ( even reworked and moved the sensor ground lug to firewall stud and grounds tied directly back to battey and block) replaced the temp sensor and tps
checked the ground to the pcm

what am I missing ?
I mean I had none of these problems unitil I swapped the tranny and PCM! I am at a total loss at this point

bad or flaky PCM???

also what is difference in the 12679525 and 12679525 TB?


anyway to check the ect fly by wire module?

Posted 4 minutes ago (edited)
man am I sick of dealing with all sorts of gremins on my 2004 GMC sierra 1500 SLE with 5.3
It all started when I replaced/rebuilt my trans. no problems there..
But I had to have the PCM reprogrammed( blackbear) becasue of the new tranny needed the stock tranmission table put back in.
I had a spare pcm that my tune was revised and loaded and I installed it.

NOTHING BUT ISSUES SINCE.

1) the fan operation was reversed after the PCM install..meaning the small fan and large fan oeration sequence were reversed
2) the TCC occasionaly does not lock up or get called to lock up( verified on scan tool) . so far its been a nuisance
3) the fugger won't ide for squat and sometiems just dies. especially if you whack the trhottle and let off in traffic lets say.. of you get off an highway ext ramp nad pupp up to stop .
it seems it cant find idle spot.

Ive checked all the friggen grounds ( even reworked and moved the sensor ground lug to firewall stud and grounds tied directly back to battey and block) replaced the temp sensor and tps
checked the ground to the pcm

what am I missing ?
I mean I had none of these problems unitil I swapped the tranny and PCM! I am at a total loss at this point

bad or flaky PCM???

also what is difference in the 12679525 and 12679525 TB?


anyway to check the ect fly by wire module?
 

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Toxic Masculinity
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Self inflicted wound... the transmission doesn't hold or store any data. The transmission shift tables are stored in the PCM and will shift the new trans exactly like it did the old transmission. The only need to reflash is if your replacing the 4L60 to a 4L80 then you'll need a segment swap and a "write entire" calibration. Put the original PCM back in and drive.
 

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Discussion Starter #3
Self inflicted wound... the transmission doesn't hold or store any data. The transmission shift tables are stored in the PCM and will shift the new trans exactly like it did the old transmission. The only need to reflash is if your replacing the 4L60 to a 4L80 then you'll need a segment swap and a "write entire" calibration. Put the original PCM back in and drive.
NOT self inflicted.. the PCM had to be reflashed TO PUT THE STOCK TRANSMISSION TABLES BACK IN from a prior mod dating back to 2011..probalby one reason the 4L60E lasted 265K
The "original" PCM has as custom tune in it, plus it was required to add electric fans to the '04.. the only thing modifed was the stock trans tables put back in in a spare pcm we had swapped out prior to the autocal system in EFI LIVE. the tune that was in the prior PCM ws kept just trans tables set back to stock
 

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Toxic Masculinity
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NOT self inflicted.. the PCM had to be reflashed TO PUT THE STOCK TRANSMISSION TABLES BACK IN from a prior mod dating back to 2011..probalby one reason the 4L60E lasted 265K
The "original" PCM has as custom tune in it, plus it was required to add electric fans to the '04.. the only thing modifed was the stock trans tables put back in in a spare pcm we had swapped out prior to the autocal system in EFI LIVE. the tune that was in the prior PCM ws kept just trans tables set back to stock
See If i'm following correctly... the original PCM had modified transmission shift tables. After the trans swap you wanted to revert back to stock shift tables?
 

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Plug the OG PCM with the tune back in. As long as the stall size wasn’t drastically change the shift tables gonna shift still.

The shift tables only control the ROMs and speeds the trans will shift. And regardless of what has been done to the trans, that’s still the same. Only the pressures tables really need to go back to stock if you built the trans.
 

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Discussion Starter #6
pressure tables were modded... that doenst explain the the rough idles stalling tcc non lockups and allsorts of other weird shit goign on
 

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Torque converters stuck, would explain idle, and all the symptoms but fans. Being an 04 it’s not factory equipment, and the PCM sends ground not power to engage fans, might just be an over sight in the tune.

Once again, you have both PCMs, put the old when in and see what happens.
 

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Discussion Starter #8
Torque converters stuck, would explain idle, and all the symptoms but fans. Being an 04 it’s not factory equipment, and the PCM sends ground not power to engage fans, might just be an over sight in the tune.

Once again, you have both PCMs, put the old when in and see what happens.
cant pressure tables are way to high for the new tranny .. and im not spending anymore money sending pcms back and forth to have programs loaded.. convertor not stuck it will dioe with tthe truck rollign and lettign off the gas.. last thing is hopefluuy wae can catch the fuel pump maybe if not im buying efi live or hp tuner and do ti meyself plus they ahve good live graphic scan so we can trouble shoot this bitch...
 

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