LBZ tune acting strange

M

Mac Daddy

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Apr 25, 2008
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A friend brought his '06 LBZ over because he got bigger tires so I made a copy of his stock tune from his truck...We changed the tire size and when I reprogrammed the ECM I noticed two interesting things:

1.) When the programming was finished the door locks and other things that make noise didn't act the same way my LMM does...Is this normal?

2.) The brakes were very soft and spongy..

Anyone have an idea what would cause this and what can I do to correct it?
 
JoshH

JoshH

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Mac Daddy said:
A friend brought his '06 LBZ over because he got bigger tires so I made a copy of his stock tune from his truck...We changed the tire size and when I reprogrammed the ECM I noticed two interesting things:

1.) When the programming was finished the door locks and other things that make noise didn't act the same way my LMM does...Is this normal?

Are you saying on your LMM the doors lock and chime sounds, etc, but on your buddy's LBZ it didn't do anything?

2.) The brakes were very soft and spongy..

How were they before you programmed it? What size tires did he put on?

Anyone have an idea what would cause this and what can I do to correct it?
Click to expand...
Responses in red.
 
M

Mac Daddy

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1.) When the programming was finished the door locks and other things that make noise didn't act the same way my LMM does...Is this normal?

Are you saying on your LMM the doors lock and chime sounds, etc, but on your buddy's LBZ it didn't do anything?


Yes on my LMM and another guy's LMM the doors lock and chime sounds; but on the LBZ nothing happens....tried it several times last night...
 
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M

Mac Daddy

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Lbz

stacks04 said:
does it run right, and speedo read correct? if yes, your job is done. if no, well you need to fix it:)
Click to expand...

Lol that is what I am trying to do is get it fixed..the brakes did not act like this before I changed the tire size...sometimes they go to the floor....just trying to see if anyone else experienced this and what was their solution.
 
dmaxfireman

dmaxfireman

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Apr 8, 2007
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what size tires and what did you enter for revs per mile. were these tires being run before you changed the tune?

i do not believe anything in efi affects the abs module. you need a tech2 to reprogram the abs module for larger tires.
 
S

stacks04

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The efi live tire size is strictly for speedo correction, nothing else. It should not have changed anything in the abs module like Kyle said above me.
 
M

Mac Daddy

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stacks04 said:
The efi live tire size is strictly for speedo correction, nothing else. It should not have changed anything in the abs module like Kyle said above me.
Click to expand...

I agree...the truck had I believe from the factory 245/70/16....he told me his speedometer was off because he put 285/75/16 on it...I changed the tire size and thats when it got crazy...doesn't make any sense to me...I have changed tire size on 2 LMM's with no issues.
 
minisub

minisub

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stacks04 said:
The efi live tire size is strictly for speedo correction, nothing else. It should not have changed anything in the abs module like Kyle said above me.
Click to expand...

I'm not so sure about that. I needed to take a business trip that was going to get me right to the edge of warranty and needed a few things looked at before it expired. To give myself a cushion to make the trip, get home and get to the dealer, I programmed really small tires into my tune.

I left for my trip, got to the red light at the end of the block and had an Oh Sh*t moment. Got stopped in time, pulled over, changed the tune back to the original tire size and everything was fine.

If Mac Daddy didn't get the tire size right within a certain window, I am thinking it could effect braking.
 
S

stacks04

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minisub said:
I'm not so sure about that. I needed to take a business trip that was going to get me right to the edge of warranty and needed a few things looked at before it expired. To give myself a cushion to make the trip, get home and get to the dealer, I programmed really small tires into my tune.

I left for my trip, got to the red light at the end of the block and had an Oh Sh*t moment. Got stopped in time, pulled over, changed the tune back to the original tire size and everything was fine.

If Mac Daddy didn't get the tire size right within a certain window, I am thinking it could effect braking.
Click to expand...

I dont know sub, there are a ton of people that have huge mudders on with the stock size programmed into the ecm. We rarely see break pedal complaints because of this at the dealer. I am curious. Cripe i just did an lbz for tire size change and there was no adverse change in break pedal.
 
M

Mac Daddy

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error

It wasn't an error on my part after all..guy took it to the dealer he explained to the service manager (who is also a friend) how the truck was acting they reflashed it and the ECM fried (good thing it happened at the dealership)...only charged him labor Warranty covered the ECM
 
wilsonck

wilsonck

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so, your buddy still has stock sized tires in the programming or did you change it back to 285's after the dealer reflash?
 
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LWATSON

LWATSON

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Jul 30, 2008
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I put a Predator on my truck when it was new, the tire size could only be adjusted up so much or this same problem would hapen to my truck.
 
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