Problem with conversion using 2005 LQ4, will not run off idle
Thread Starter
Launching!
Joined: Sep 2009
Posts: 250
Likes: 3
But, I've gotten to "play" a little bit with the engine and still confused.
With the stock 6.0L tune with VATS removed, the TB moves when the pedal moves... both with the engine running and with the engine not running.
Thread Starter
Launching!
Joined: Sep 2009
Posts: 250
Likes: 3
Here is some of the info I've been able to find that differs between the 4.8L with stick and 6.0L with auto(4.8 on left, 6.0L on right, please excuse formatting):
Fuel Parameters
Power Enrich Mode Delay 3 Sec 60 Sec
DFCO Enable RPM - Clutch Based 900 RPM 10000 RPM
DFCO Disable MAP - Clutch Based 104.98 Kpa 0 Kpa
DFCO Disable %TPS - Clutch Based 8.01 % 0 %TPS
DFCO Disable MPH - Clutch Based 7 MPH 200 MPH
System Parameters
Abuse Mode Test Enable RPM 6600RPM 1400 RPM
Abuse Mode Test Disable MPH 0 MPH 128 MPH
Abuse Mode Enable %TPS Threshold 31.99 %TPS 76.8 %TPS
Abuse Mode Enable RPM 4800 RPM 7000 RPM
Abuse Mode Enable Speed 255 MPH 55 MPH
Abuse Mode Test Disable RPM 6500 RPM 1200 RPM
Diagnostic Parameters
Low TPS Diagnostic Min MAP 55 Kpa 65 Kpa
High TPS Diagnostic Max MAP .7 Kpa 55 Kpa
Idle Control Parameters
Throttle Cracker Disable Speed 1 MPH .75 MPH
Min. IAC Correction - in P/N 0 gm/sec -3 gm/sec
Max. IAC Correction - in P/N 0 gm/sec 4.5 gm/sec
Default Learned IAC Offset - in P/N 0 gm/sec .5 gm/sec
Min. IAC A/C Offset Correction - P/N 0 gm/sec -.4 gm/sec
Max. IAC A/C Offset Correction - P/N 0 gm/sec .5 gm/sec
I have ignored all the fuel/spark related tables because there is no trusted way to tell if the difference is because of the engine size or the transmission.
Anyone got an idea?
Fuel Parameters
Power Enrich Mode Delay 3 Sec 60 Sec
DFCO Enable RPM - Clutch Based 900 RPM 10000 RPM
DFCO Disable MAP - Clutch Based 104.98 Kpa 0 Kpa
DFCO Disable %TPS - Clutch Based 8.01 % 0 %TPS
DFCO Disable MPH - Clutch Based 7 MPH 200 MPH
System Parameters
Abuse Mode Test Enable RPM 6600RPM 1400 RPM
Abuse Mode Test Disable MPH 0 MPH 128 MPH
Abuse Mode Enable %TPS Threshold 31.99 %TPS 76.8 %TPS
Abuse Mode Enable RPM 4800 RPM 7000 RPM
Abuse Mode Enable Speed 255 MPH 55 MPH
Abuse Mode Test Disable RPM 6500 RPM 1200 RPM
Diagnostic Parameters
Low TPS Diagnostic Min MAP 55 Kpa 65 Kpa
High TPS Diagnostic Max MAP .7 Kpa 55 Kpa
Idle Control Parameters
Throttle Cracker Disable Speed 1 MPH .75 MPH
Min. IAC Correction - in P/N 0 gm/sec -3 gm/sec
Max. IAC Correction - in P/N 0 gm/sec 4.5 gm/sec
Default Learned IAC Offset - in P/N 0 gm/sec .5 gm/sec
Min. IAC A/C Offset Correction - P/N 0 gm/sec -.4 gm/sec
Max. IAC A/C Offset Correction - P/N 0 gm/sec .5 gm/sec
I have ignored all the fuel/spark related tables because there is no trusted way to tell if the difference is because of the engine size or the transmission.
Anyone got an idea?
Thread Starter
Launching!
Joined: Sep 2009
Posts: 250
Likes: 3
If I were going to use diag software, what would be the logical things to keep an eye out for?
RPM is one. Throttle position sensor is another.
What about engine load? Timing Advance? Air flow? Intake pressure?
Will monitoring the front o2 sensors help me at all?
For example, I know the following:
Throttle position starts at ~8% with no throttle. And goes to 100% for WOT.
Can someone explain the range of values for these and what the numbers mean?
What is the range for engine load? In my tests, I've gone from 2% to 25%.
What is the range for timing advance? In my tests, I've gone from 18.5 to -2.5.
What is the range for air flow? In my tests, I've gone from .8 to 11.7. I'd guess that as the TB goes wide open, this number goes up. So there should be some direct correlation to TP%.
What is the range for intake pressure? In my tests, I've gone from 10 to 29.5.
If I am at idle, what should engine load%, timing advance, intake pressure, and air flow be at? In my case, engine load is at 2.0%, timing advance is 18.5, intake pressure is at 10.0 and air flow is at .8.
When I stab the throttle, the engine stumbles badly. The TPS is at 99.6%, the engine load is 25.5%, the timing advance goes to -2.5. Intake pressure goes to 29.5 and air flow goes to 11.7.
Has anyone tried disconnecting the plug from an auto tranny then run the engine on a stock LSx tune? Did it run at all?
And completely unrelated to tuning issues, will a clogged fuel filter/regulator still allow for proper fuel pressure but not enough flow for any throttle?
RPM is one. Throttle position sensor is another.
What about engine load? Timing Advance? Air flow? Intake pressure?
Will monitoring the front o2 sensors help me at all?
For example, I know the following:
Throttle position starts at ~8% with no throttle. And goes to 100% for WOT.
Can someone explain the range of values for these and what the numbers mean?
What is the range for engine load? In my tests, I've gone from 2% to 25%.
What is the range for timing advance? In my tests, I've gone from 18.5 to -2.5.
What is the range for air flow? In my tests, I've gone from .8 to 11.7. I'd guess that as the TB goes wide open, this number goes up. So there should be some direct correlation to TP%.
What is the range for intake pressure? In my tests, I've gone from 10 to 29.5.
If I am at idle, what should engine load%, timing advance, intake pressure, and air flow be at? In my case, engine load is at 2.0%, timing advance is 18.5, intake pressure is at 10.0 and air flow is at .8.
When I stab the throttle, the engine stumbles badly. The TPS is at 99.6%, the engine load is 25.5%, the timing advance goes to -2.5. Intake pressure goes to 29.5 and air flow goes to 11.7.
Has anyone tried disconnecting the plug from an auto tranny then run the engine on a stock LSx tune? Did it run at all?
And completely unrelated to tuning issues, will a clogged fuel filter/regulator still allow for proper fuel pressure but not enough flow for any throttle?
Thread Starter
Launching!
Joined: Sep 2009
Posts: 250
Likes: 3
Problem somewhat solved. The issue is indeed a tune issue. Using the 4.8L manual tune that poconojoe provided, I was able to identify the above differences. I changed those values in my tune and flashed the PCM.
Fired up and throttle response is NICE.
So, there is something different in an auto tune that will cause the LQ4 to idle fine but not run off idle. I'm not sure which of the following groups listed above really helped the issue:
Fuel Parameters
System Parameters
Diagnostic Parameters
Idle Control Parameters
It should work until I can have the time and money for a professional "mpg" tune done.
With the above said, if anyone can point me to a stock LQ4 tune with a manual trany, it would be GREATLY appreciated.
Fired up and throttle response is NICE.
So, there is something different in an auto tune that will cause the LQ4 to idle fine but not run off idle. I'm not sure which of the following groups listed above really helped the issue:
Fuel Parameters
System Parameters
Diagnostic Parameters
Idle Control Parameters
It should work until I can have the time and money for a professional "mpg" tune done.
With the above said, if anyone can point me to a stock LQ4 tune with a manual trany, it would be GREATLY appreciated.
Teching In
Joined: Dec 2008
Posts: 40
Likes: 0
From: In the Woods
He does business on eBay, his name is Rodney, and his e-mail is Dlcrewchief63REMOVE@aol.com. (Remove the "REMOVE" from the e-mail address above to get it to work...I don't want him getting spaminated on account of this post.)
Might be worth a try anyhow,
Jake
