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PSWired
January 6th, 2005, 06:00 AM
Hi everyone, I am planning to purchase FlashScan soon to use on a project I am undertaking. I'm installing a 2002 LQ9 (6.0L 10.1:1 compression genIII truck engine, used in escalade and SS) along with a 4L80e transmission (used in 3/4 ton and heavier pickups) using a 2002 PCM and wiring harness from a 3/4 ton truck into my 95 chevy pickup. I need to come up with a PCM image that will support the 4L80e and have calibration that will run the higher compression LQ9. Would I be able to take the calibration on my PCM now, for a low compression 6L motor and 4L80e, and copy the engine tables from another vehicle equipped with an LQ9 motor easily with EFILive's offerings? If not, what is the best way to go about doing this?

My next question regards electric fan control. I'd like to use the PCM to control my electric cooling fans. I see the camaro LS1 computers have a provision for two speed fan control. Is there a way to make this feature work with my 2002 truck PCM? Of course I would have to add pins to the PCM connector and what not. Thanks in advance.

Patrick

Steve Bryant
January 6th, 2005, 06:32 AM
Patrick,
The short answer is yes, I believe that it would work with some trial and error on your part. I have been one of the Beta Testers and I have a 2000 Yukon XL (K2500) with the LQ4 and 4L80E. The Basic calibration that is in the PCM you have for an LQ4/4L80E can be modified for the LQ9 by advancing the high and low octane spark tables for 91 octane fuel (as a starting place, you could copy the values directly out of a 2002 Escalade). I'm pretty sure that the fan functionality exists in the PCM already, you just have to go into the fan table and enable it (it will be disabled for the truck application initially) and add the pins, wiring interface and fuse(s) plus the fans.

All my best,
Steve

SinisterSS
January 6th, 2005, 09:07 AM
Steve's EFILive file with the 4L80E and the file of my SS with the LQ9 are posted here (http://stealthv.nitro-nights.com/tunes.htm). 8)

PSWired
January 6th, 2005, 09:38 AM
Wow thanks for the quick reponses! Now does anyone know if the truck PCMs support the two speed fan control or just single speed?

PSWired
January 6th, 2005, 09:40 AM
Oh and one more thing... will I run into any licensing problems reading other files to compile into one? I.E. do I need to use one PCM license per file read?

SinisterSS
January 6th, 2005, 10:43 AM
Licenses are only used when you flash. You can read any supported vehicle you can get your hands on for "free". :D

Here's a screenshot of Steve's 2000 stock tune with the fan settings.

GMPX
January 6th, 2005, 12:12 PM
Licenses are only used when you flash. You can read any supported vehicle you can get your hands on for "free". :D


I have actually considered going into the local GM dealer and 'test driving' the latest car just to dump the cal out...c'mon, you know you want to as well!!.
Might even reflash it for them so the next real customer gets a surprise when the thing steps sideways on a 1-2 shift :lol: :lol:

Cheers,
Ross

wait4me
January 6th, 2005, 12:23 PM
lol i wish someone would have done that for me when i got a new car.. lol you would think that dealers would try to promote computer mods as a special to the customer.. :) i would deffinatly buy a faster stock vehicle than a slow one..

Steve Bryant
January 6th, 2005, 01:27 PM
Patrick,
I opened Rick's 2004 Silverado SS .tun/bin file and have looked at the fan functionality (actually this aspect hasn't changed much since my 2000). I've done a screen copy below so you can look at what you would need to do. You would enable the fan operation and set the parameter values, save the .tun file and "download"/flash the PCM. Then, with the wiring and electric fans in place, it should work like a champ.

Then I also did a screen dump showing the high octane spark table (I turned the 3D map so you could see the contour of the table better - this is easy to do and only takes a couple of seconds). You can copy this whole table by clicking on the upper left hand cell (A1 position which is blank) in the 2D table and select copy, then go to the same table for your 2002 PCM and click on cell A1 and select paste and all the values go right into your 2002 High Octane Table. Then you'll want to further optimize this and some other tables, but that's a lot of the fun and learning experience!

Steve

PSWired
January 6th, 2005, 02:16 PM
Dang, you guys are just full of information! This PWM fan control has my interest. If I come up with the proper solid state switching circuitry to modulate the fan power, will my 2002 truck PCM support this feature? What pin numbers on the PCM would I use for this feature or the series/parallel fan wiring setup?

Steve Bryant
January 6th, 2005, 02:21 PM
I'm not sure, but I'd be glad to help you figure it out.

All my best,

Steve

GMPX
January 6th, 2005, 02:22 PM
Dang, you guys are just full of information! This PWM fan control has my interest. If I come up with the proper solid state switching circuitry to modulate the fan power, will my 2002 truck PCM support this feature? What pin numbers on the PCM would I use for this feature or the series/parallel fan wiring setup?

Sorry, PWM fans were on 2003+, which is a different PCM to the 2002.

Cheers,
Ross

wait4me
January 6th, 2005, 02:25 PM
ive looked thru every computer wiring output for every 2002 and down truck :) and it must be a software switch that has to be turned on to make a numbered wire turn into a fan turn on output switch. it would be a negative signal from the pcm, so maybe, if it is in the system and just not printed anywhere, you could set the fans to come on at 50 degrees, so you would know it should be on, and then probe all the unused pins on the pcm to see if they are a switched ground output and then verify it with scanner and turn the fans on and off and it should show that on the test light...?? unless it would be the same output as a camaro or corvette pcm? i guess ill look more... jes

SinisterSS
January 6th, 2005, 04:50 PM
2005 trucks have electric fans, my 2003 still has the 'old-fashioned' off the water pump.

Would be nice to find a 2005 truck and "suck its brains" to get the factory fan settings.

Can we rename the "Read calibration button" to that Paul?

SinisterSS
January 6th, 2005, 05:01 PM
For an electric fan retrofit, I think you'll find this thread interesting...

Fans on Silverado SS Forum (http://www.silveradoss.com/forums/index.php?showtopic=9616&hl=electric++fans)

Blacky
January 6th, 2005, 10:29 PM
2005 trucks have electric fans, my 2003 still has the 'old-fashioned' off the water pump.

Would be nice to find a 2005 truck and "suck its brains" to get the factory fan settings.

Can we rename the "Read calibration button" to that Paul?

Can you imagine the panicky support calls we would get if the button was called "Suck its brains"? :D :D

Paul

GMPX
January 6th, 2005, 10:53 PM
Would be nice to find a 2005 truck and "suck its brains" to get the factory fan settings.

You'd be dissapointed Rick (well for a short while), it's the same O.S as your CTS-V!!.

Cheers,
Ross