LS1B Operating System Upgrade Help

[fleshe]

Here's a small rundown of what I need help with. Along with the PCM files that will and won't run the car.

I'm currently working on a 93 LT1 Camaro that has the Torq-heads 24x Conversion kit. The PCM that has been wired to the car is a 12200411 with H/W Version 09386530.

I got the car to run on the factory 9381344 OS that came on the PCM by coping over all the calibrations from the 02 Chevy Express Tune that runs OS 12212156. I manually copied over all the compatible calibrations and the car starts and runs fine. Here's where I start to run into the problems. I want to upgrade to COS5 for Nitrous reasons. Since the 9381344 OS is not an upgradable OS I decided to Flash the PCM with the 02 Express Van tune I orginally copied all the calibrations from. The 02 Chevy Express van runs OS 12212156 which is a compatible OS with COS5 and it will allow me to copy over the calibrations I planned on adjusting before the COS5 upgrade to get the car somewhat on a decent tune. But, everytime I upgrade to OS 12212156 the car will not start. I have fuel but no spark. If I reload the 9381344 OS flash, the car will start and run just fine.

What am I doing wrong?

[joecar]

I think that 12212156 might not be compatible with your PCM...

let me look thru your 12212156 ctz.

[fleshe]

I think that 12212156 might not be compatible with your PCM...

let me look thru your 12212156 ctz.

Thank you for lookin at the files.

[joecar]

I looked briefly, I didn't see any reason for the no-start... I'll keep looking.

[fleshe]

I looked briefly, I didn't see any reason for the no-start... I'll keep looking.

Do you have any suggestions Joecar? Or maybe know of a compatible OS that is upgradable with this specific PCM?

[joecar]

During start/cranking:
- does scantool show rpm (in real time)...?
- does fuel pump run...?
- do injectors fire...?
- do spark plugs fire...?



I'm wondering if VATS is interfering...

[fleshe]

I will check all these items 100% this week and get you an answer


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[ProperTuningOG]

Running H/W Version 09386530 with 02020005 in about 20 different ecms just this year....... Just an FYI for compatibility

[fleshe]

Running H/W Version 09386530 with 02020005 in about 20 different ecms just this year....... Just an FYI for compatibility

Thank you!


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[ProperTuningOG]

Will it fire with just an OS swap? Not copying everything over.

I also know I have never had any luck running maflass with 2156 and having the DTC to C non emissions. I've always used A.

After your full flash are you getting a true power cycle? Have you tried cal flash after the full flash?

[fleshe]

I did try to flash over the factory Chevy Express Van tune with no changes other than vats disabled and it still would not start.

[ProperTuningOG]

You can’t do that. The conversion is 24x based not vortec 5.7 low res. An 02 express still ran a 5.7 vortec.

[joecar]

I'm not familiar on what the trucks/van run, but Team208MS has a point, incompatible CKP signals... this will most likely be the reason for no start/run.

[ProperTuningOG]

You have to modify a ls based tune for the conversion. Start with a truck 2156 5.3 and copy over info from there.

[ScarabEpic22]

Agreed with Team208Motorsports and late to the party here.

Looking at the TorqHeads 24x conversion kit, it runs the regular 24x/1x LS1 style setup not the low res the Express 5.7L/350 SBC uses. You need to use whatever base file it came with (Truck, F-Body, Vette) to keep the plug n play wiring. I'd guess F-Body or Truck, so grab a truck 12212156 OS and try that. Either 5.3 or 6L with appropriate trans segment and full flash it.


I'm not familiar on what the trucks/van run, but Team208MS has a point, incompatible CKP signals... this will most likely be the reason for no start/run.

Joe, the 02 Express Vans have a 5.7L SBC and the universal OS 12212156 which allows anyone with a SBC to easily run a LS1 512kb PCM and COS5. I.E. 96-00 Tahoe/Suburbans / C/K trucks that came with the Vortec Black Box PCM.

[fleshe]

I will execute these steps this weekend. Thank you all so much for the amazing knowledge and help!

[RonnieW]

I will execute these steps this weekend. Thank you all so much for the amazing knowledge and help!

fleshe,
What did you end up using? I have a similar situation and need some help also. I did make a post. Do you have a tune file I could try?

Thanks

[fleshe]

fleshe,
What did you end up using? I have a similar situation and need some help also. I did make a post. Do you have a tune file I could try?

ThanksPM me your email and I'll send you the tune file.

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[RonnieW]

PM me your email and I'll send you the tune file.

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PM sent, maybe twice. Thanks for the quick reply!