07 chevy classic 4.8 2wd. "Nightmare"

I have been working on this truck for awhile now. It was brought to me after numerous shops attempted to fix it. All they did was butcher it. It was hit by lightning. So when I got it there was a stack of modules in the seat, truck dismantled, wires looked like spaghetti. Long story short finally replaced BCM, ECM, TAC Modules,etc. Fuel pump, injectors, coils. That's a lil history. My question is I can run injector balance test. Truck will crank and run for about 10 seconds, then dies. Then it's a crank no start. But its almost like it wants run?

The injector balance test should be a bi-directional test in the PCM. Where you find the function exactly will depend on the scanner you're using. If you've never done one before, you just install a pressure gauge on the rail and hit the magic buttons on the scanner.

Speaking of a pressure gauge, have you observed fuel pressure during the start-stall-no start? Any fault codes?

Sorry I didn't clarify. I was using Snap On Solous Ultra. I had the fuel gauge hooked up as well. The fuel pressure was within specs , based on All data. It never dropped below 60 psi while cranking. It also stayed within specs when it did run for the 10 seconds after Injector balance test.

It did throw MAF code and oil pressure code. I tried unplugging the MAF with no Avail

Look in engine control module data see if the vehicle is cutting fuel for theft mode. Think it’s called vtd fuel disable. Should stay no not go to yes. Next can you keep it running with alternative fuel to see if that’s why it stalls.

I was also thinking maybe the Theft mode , was disabling fuel. Upon further inspection I noticed the MAP sensor is bad. I am hoping this will be the issue. I'll have another one tommorow and go from there. Thank you for the response. This has been a huge job fixing all the problems caused by Lightning and other shops.

MAP sensor. "She's A Runner!!"

Interesting! What about the MAP sensor made you suspicious?

I was positive that fuel and firing system was good. Then as I was watching data, while cranking I noticed the MAP sensor data pid did not change while cranking. Can't remember exact numbers but it was around like 10 kpa. Then I checked powers and ground, all was good. Then I checked Resistance of Map sensor key off, it was well below resistance spec via Alldata. Customer was stoked to come and drive the truck home. It was Towed in on the hook, nothing worked on the truck when I received it. Stacks of parts and modules laying in the seat. Several shops fired the parts Cannon at it. The other shops had it over a year and half.

Last chance automotive wrote: Can't remember exact numbers but it was around like 10 kpa.

That's way too low. Should be around 100 KOEO and 90ish cranking.

That's right Matt T. When I saw it was at 10 ish I knew I had a problem with MAP sensor. Especially when it didn't rise at all while cranking.