LB7: Surging after Lockup

[Dura-Ration]

I have a surging at highway speeds of 55mph & up. It seems to be worse when engine is still cool & right after Torque converter lockup. It will continue to do this until it reaches 195*. And then it will be occasional. This has begin going on for about 5 months, but recently gotten worse. Any suggestions would be helpful. Is there a sensor that is dirty or something else ? One more thing, it was doing this before the Allison was built to stage 4.

 

[LBZ]

Does it do it with stock tuning?

 

[skintback]

Mine seems to do the same thing I think it's do to the LBZ pump on a LLY/LB7 and a slightly moded reg mine does it after the converter locks 48-55mph then goes away. It is annoying

 

[Dura-Ration]

Well maybe not. I'll have to try my stock tune to find out. But Like Skintback said I do have a LMM CP3. And it idles up and down on the stock tune.

 

[skintback]

You need to paly with B1010

 

[Dura-Ration]

Well I tried the stock tune and it made it less noticeable but still there. Play with B1010 ? I looked at it, but I don't want to play. :badidea:
:help:

 

[TrentNell]

Well I tried the stock tune and it made it less noticeable but still there. Play with B1010 ? I looked at it, but I don't want to play. :badidea:
:help:

Start with copying a LBZ table and pasting it in your LB7 tune . from there, if that is not enough............ you need to log, " MM3 per second" ( GM.FUELQ_MAIN_DMA ) and find the amount of MM3 per sec that the surging occurs @ and increase the "MA" per that box .

 

[Dura-Ration]

whoa nelly. me no undertan efi the live. MM3 7 dma per second What ?
I appreciate the help but I would have a melted motor by the time I figured it out. I'm mechanical not compootered.
The surge feels like a cylinder has a miss. I have logged a tune several times and have found nothing. But what do I know.

 

[TrentNell]

whoa nelly. me no undertan efi the live. MM3 7 dma per second What ?
I appreciate the help but I would have a melted motor by the time I figured it out. I'm mechanical not compootered.
The surge feels like a cylinder has a miss. I have logged a tune several times and have found nothing. But what do I know.

Post up a log , if you cant see the rail pressure fluctuate when the surge happens the previous mentioned fixes will not work . If you cant work EFI then contact who you bought it from to see if they can help out .

 

[Dura-Ration]

Thank you Trent for the help. How's the engine build going?:thumb: