dimetweaker

iTrader: (1)

Alright, finally worked out all my kinks in my swap project, several of my problems being compatible sensor wiring, etc. So, a question for the tuners since they would see this the most;

I have a LS3/L92. Started with a L92, installed a conventional cam (229/240, 625/.615 lift, 114+4). compression is around 10.3:1. Stock truck manifold, stock injectors. Its being run by the GMPP harness and ECU, with the tune loaded from GM for a stock LS2/3. Do you think it would at least start with the stock tune in it? I get it to fire to life for a rotation or 2 and then it dies off. Sometimes it sputters for 2 seconds but then its out again. Not throwing any codes, just wont come to life. Yay or nay?

94 White T/A

I'm no expert by any means, but I would think it should run. I've seen many larger cams run and drive on the stock tune.

I could be completely wrong though so take my thoughts as a grain of salt

Camaro9969

iTrader: (12)

Yes it would still run with a cam and a stock tune thats not the issue. You check all the grounds? 90% of the time thats what it is.

gagliano7

Are you using the stock truck injectors and what motor are they from? You probably have the wrong injector data . You would need the truck injector data for it to run correctly.

dimetweaker

iTrader: (1)

I've checked grounds, but I will again. The truck injectors are from a 2008 escalade. I've pulled the rails out of the motor and rolled the motor over, they all have a nice spray pattern when cranking. I figured if nothing else, it would eventually load up with enough fuel to run... But I would imagine the data is wrong. I hadn't given that much thought

Bowtie316

iTrader: (1)

I wouldn't think a gmpp ecm would have vats enabled, but thats what it sounds like.

I have started up a non-flex fuel 5.3 (24.8 lb/hr) on an untouched flex fuel 5.3 pcm (33 lb/hr) before. It didn't start great, but it did fire and run okay.

Is the maf hooked up on the intake, that can make it hard to start?

dimetweaker

iTrader: (1)

well... MAF is hooked up just to get a signal, but there isn't an intake tube on the motor. its just sitting there....

dimetweaker

iTrader: (1)

just went out and rolled it over again with the scanner on it, and when it first starts to run, voltage still hasn't recovered above 11.5 volts yet, then it dies and voltage jumps back up. Its back on the charger; how many volts does the computer need to see to run??

dimetweaker

iTrader: (1)

Problem solved!!! cut off a 20" piece of 4" PVC, stuffed the MAF in there, and away she went. Im sure that was it. I cleaned all 8 injectors again before trying this, but im sure it was having a good air signal over the MAF. I was just too excited to try and start it once all the wiring and such was done. Lesson learned!

Bowtie316

iTrader: (1)

Yeah if the maf is plugged in but not disabled in the tune, it will use it for air measurements and it won't run.