Fuel trims and P0200 code on 5.3L

[fastline]

Friend of mine is using a 5.3L truck engine and PCM in a retrofit app in an older car. I believe comp cams flashed the PCM to delete the post cat O2s and tuned it a bit.

The engine is absolutely brand new but has not run in 5 yrs. After install, engine runs but is obviously fat and throws a P0200 code. Verified all power and grounds are good to go. NOID shows good to all injectors BUT fuel trims are at -95%! The engine was tuned for the factory truck intake but an LS1 intake was added for clearance which was verified to flow a bit less.

I was thinking as well we might have some stick injectors with that kind of trim or possible the tune is now all wrong with the other intake?

Thoughts? I would like to know how high/low the fuel trims can operate before a code is set? I think the PCM is doing it's job and searching for a reason to have to reduce fuel by 95% thus throwing the P0200. I would really like to know the numeric difference in flow between the truck and LS1 intakes as well.

[bangbangskeetskeet]

I highly recommend having someone other than comp cams do the tuning of the PCM.

[RedHeartbeat]

check the FPR and see if it's leaking into the intake. Pull the vacuum hose off it while its running and see if it is pushing fuel out the regulator's vacuum port.

[GasGuzzler]

P0200 is an electrical issue, not a tune issue. It's odd it doesn't set a P020X with X being 1 through 8. I'd say one or even more of the injector control circuits to the PCM are wired incorrectly to ground (holding it/them wide OPEN) instead of having the PCM control it/them (injectors are powered all the time and turned off and on by ground supply by the PCM). This would explain a GENERAL injector control DTC as well as a -95 FT (although I thought about +/- 30 or so was max).....