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goldenhp
September 11th, 2011, 01:42 PM
what would you guys suggest for tuning idle. the problem i have is that when i put it in gear it will chugg like its about to die. then when i let off the gas it lunges forward and then it fine what could cause that. then after that when put in gear it would lightly slam into gear.
This vehcile is a 2000 chevy 1500 with a 5.3 with a comp cam (small cam a bump up from stock.
Also when i do a pull on the truck it will pull 8 degress of timing but i turned it down to only pull 1 degree and truck got better with no sign of detenation whatsoever. the knock sensor are new sensors soooo.... any ideal what that could be?

etmotorsports
September 11th, 2011, 02:58 PM
Data log it and post it up

goldenhp
September 12th, 2011, 01:04 AM
this is the issue im talking about. Im not sure what its doing but i wanna get it cleared up. So if you have any suggestion on what i can do to remedy this problem. Heres my tune for reference, Thanks in advance

Sid447
September 12th, 2011, 05:17 PM
The tune file,

looks to be a bit strange. If you have a small cam then it would probably run better on the stock tune file if your maf-sensor is in good condition.
As an alternative you could download the 2000 Camaro SS-A4 or the Lumina SS-A4 file which has the same OS as you do (09381344) from here:

http://www.tunefiledepot.com/index.php?option=com_content&view=article&id=4&Itemid=3&Manufacturer=3&VehicleType=P&Stock=Y


You'd need to change over some tables before using it:

{B0104} Change from 708 to 666.
All injector tables from your truck file to the Camaro file.
Tyre and diff re-calculation to get your trans cal correct.

....Can't think of any others off the top of my head but it's worth a try and see no reason why it shouldn't work.
Though the High Octane Table used in the 2000 Camaro (and Lumina SS) might be a bit adventurous for a 5.3 in a 2-ton truck, you might want to copy and paste the 2001 ZO6 HOT into the Camaro or Lumina file which should be safer.



(http://www.tunefiledepot.com/index.php?option=com_content&view=article&id=4&Itemid=3&Manufacturer=3&VehicleType=P&Stock=Y)

The Alchemist
September 12th, 2011, 11:01 PM
11939

B4703 in gear airflow needs to be higher than in neutral to take the load of the trans. Do the RAFIG process to set this up correctly this will make idle transitions spot on. Add 2g/s to the whole in gear table reflash and start from there.
Your throttle cracker table looks way to high. This will cause the car to feel like it surges foward when you are off the gas. Log where this happens at what speed and rpm and adjust this table downwards until you get a nice slow decel when off the gas. Make broad changes at first like 1g/s until you feel a change then fine adjust in 0.2g/s increments. I have included a good cracker table in the tune below that will put you in the right direction. They take a while to set up on the road but are worth getting right....
Timing also affects this decel feel so look at your spark table and maybe decrease spark in the decel area. Remember that max timing anywhere can only be less than 40deg so change all your 50's & high 40's in your spark high & low maps down to 40 then adjust downwards from there according to the feel when decelerating> aim for 25 to 30 deg in the decel areas.


what would you guys suggest for tuning idle. the problem i have is that when i put it in gear it will chugg like its about to die. then when i let off the gas it lunges forward and then it fine what could cause that. then after that when put in gear it would lightly slam into gear.
This vehcile is a 2000 chevy 1500 with a 5.3 with a comp cam (small cam a bump up from stock.
Also when i do a pull on the truck it will pull 8 degress of timing but i turned it down to only pull 1 degree and truck got better with no sign of detenation whatsoever. the knock sensor are new sensors soooo.... any ideal what that could be?

goldenhp
September 13th, 2011, 07:17 AM
11939

B4703 in gear airflow needs to be higher than in neutral to take the load of the trans. Do the RAFIG process to set this up correctly this will make idle transitions spot on. Add 2g/s to the whole in gear table reflash and start from there.
Your throttle cracker table looks way to high. This will cause the car to feel like it surges foward when you are off the gas. Log where this happens at what speed and rpm and adjust this table downwards until you get a nice slow decel when off the gas. Make broad changes at first like 1g/s until you feel a change then fine adjust in 0.2g/s increments. I have included a good cracker table in the tune below that will put you in the right direction. They take a while to set up on the road but are worth getting right....
Timing also affects this decel feel so look at your spark table and maybe decrease spark in the decel area. Remember that max timing anywhere can only be less than 40deg so change all your 50's & high 40's in your spark high & low maps down to 40 then adjust downwards from there according to the feel when decelerating> aim for 25 to 30 deg in the decel areas.
is that a attach file?

The Alchemist
September 13th, 2011, 07:29 AM
I hope so :) changed a few things for you as per suggestions above. Saves you mucking around for another few hours :)

goldenhp
September 13th, 2011, 11:28 PM
I hope so :) changed a few things for you as per suggestions above. Saves you mucking around for another few hours :)

thanks a ton, that helped out a whole bunch and i believe the truck is running 100 percent better as well. so thanks so much and i can see all the changes

The Alchemist
September 14th, 2011, 07:20 AM
Hey, no probs. Happy to help :cheers: At the end of the day it all about HOW the car drives I think. I spend a lot of time getting this right on each car i tune. Probably more on road time that dyno time actually...