Vortec 454 rough starting and idling

[Derpy Dylan]

Hey strangers. I've got a 97 Vortec 454 stick shift 4x4 truck. Only engine mods are a short ram intake and cat-back exhaust, nothing major. I just did the 0411 PCM swap this week. I'm having issues with it now. I have verified the pins and wiring, it's all good. I bought the wiring diagram, PCM, and new connectors from Lextech, the guy that came up with this swap for the GMT400 platform. He put a tune on the PCM and disabled the VATS for me before he sent it out. He uses EFI life if that matters. He said he used the same tune that he's used for over 30 different 454 trucks like mine, and that it's been tried, tested, and refined. So the tune shouldn't be an issue. My truck seems to run good when I rev it up, but the idling and startup are ROUGH. It won't start without the gas pedal, and half of the time wont idle without it either. In the log, every time it died is when I let off the gas pedal. It doesn't take much pedal, but it takes some. Anyway, here's the tune and the log. Let me know what you think please. Any help would be appreciated. Thanks

EDIT: I want to also mention that I?m getting codes P0101, P1336, and P1345 consistently. Sometimes it idles smoother if I use special functions to force closed loop, but still a good idle. I?ve tried to do the crank relearn but with it running so poorly and dying, it?s not working

[5FDP]

It's super rich, the o2 sensors are really high and then when you forced closed loop the fuel trims are removing 34% worth of fuel to help it out.

Is the injector data correct for this engine? Just want to make sure that you are running the same size injectors that the tune says it is.

If that is good and you are not getting too much fuel pressure you should try to pull some fuel away from the MAF airflow curve. It kinda looks like someone just added a bunch of fuel to it.

[Derpy Dylan]

To be honest, I?m not sure if the injectors are the same as what?s in the tune. As far as I know there?s nothing done to my engine besides the short ram and cat back, and it?s a low mileage crate motor from a parts store so everything should be OE. The tuner says this tune is tried and true with these motors so I?m trying to eliminate everything else before messing with the tune itself, because if the tune really is good then there?s something else wrong

[blindsquirrel]

Find out and fix what's causing the P0101 & P1345 before you go looking high and low for anything else. Basic diagnostics - fix the known problems and then reevaluate.

[Derpy Dylan]

It ran fine and didn?t have those codes before. And I can?t fix the crank sensor code until it?s running better because it?s impossible to do the relearn like this

[blindsquirrel]

P1336 is the CKP variation not learned. P1345 CKP-CMP correlation is unrelated to not having done the relearn. You need to follow the diagnostics for the P0101 & P1345. Only after P1345 is no longer a current code will it allow you to do the relearn and get rid of the P1336.

[Derpy Dylan]

I thought I had a win for a minute earlier. I upped the injector size to 26lb/hr and it was actually idling! I don?t know what injectors are in this thing so I was just trying shit. But the engine was still cold, once it was fully warmed up it started doing the same thing. Reads lean as hell when you try to let it idle, and it more often than not dies because of it. So I enabled RTT and tried adding fuel to the idle areas, still dies out. Idle areas are lean as can be and everything above is pig rich no matter what I do. I have no idea what?s going on with this thing. I don?t have the MAF codes anymore

[Motorsports-X]

I thought I had a win for a minute earlier. I upped the injector size to 26lb/hr and it was actually idling! I don?t know what injectors are in this thing so I was just trying shit. But the engine was still cold, once it was fully warmed up it started doing the same thing. Reads lean as hell when you try to let it idle, and it more often than not dies because of it. So I enabled RTT and tried adding fuel to the idle areas, still dies out. Idle areas are lean as can be and everything above is pig rich no matter what I do. I have no idea what?s going on with this thing. I don?t have the MAF codes anymore

if that tune has been proved out on stock trucks and yours isnt running right, its likely becuase you have a mechanical issue in the truck. most likely a vaccuum leak. check around and see if you can find anything before you start messing with the tune too much.

[Derpy Dylan]

I?ll check for vacuum leaks again tomorrow. I just have to assume that it?s tune related because the truck ran great before

[Motorsports-X]

I?ll check for vacuum leaks again tomorrow. I just have to assume that it?s tune related because the truck ran great before

maybe you missed a pin? check all cylinders are firing. go through your pinout sheet one line at a time and check every pin.

[2xLS1]

Was the short ram intake on it when it ran fine before?

[Derpy Dylan]

Yep

[Derpy Dylan]

I?ve checked the pins 6 times, they?re all good. No blown fuses either