Crank but No Start

[T-Bird]

Have a 2006 chevy silverado. Driving and it just died. Things I have done. Replaced the fuel pump. Getting plenty of fuel pressure at the fuel rail. Still won't start. Replace the camshaft sensor, still won't start. Replaced the crankshaft sensor, still won't start. Replaced the ECM, still won't start. Checked all the fuses. Checked the fuel pump relay. Nothing. 

Put some starting fluid in the throttle body, cranks up. Try again without the starting fluid, Nothing. Def seems like a fuel issue, but I can't find the issue. Have asked 3 different mechanics, they have no idea now either. Truck will turn over, but will not start without gas or starting fluid. AM I missing something? TYIA...

[CamGTP]

The theft system could cause a no start but with a new computer that is unlikely now.

 

I'd be looking at scan tool data to see what some of the sensors are saying. Easy stuff to try is unplugging the MAF and trying to start it.

 

 

[T-Bird]

No doubt. I actually tried the "theft system" reset, even though i had the new ECM installed. I scanned the truck, no codes except for a, O2 sensor. You think the MAF could possibly be holding the fuel out? TU.

[CamGTP]

It's possible, unplugging the MAF is just a test to see if a bad MAF reading is causing it to not run.

[T-Bird]

Ok. I’ll try that in the morning. Just unplugging the MAF sensor will allow it to startup if the sensor is out? I appreciate the response. 

[richard wysong]

Do you have power (12v) at the injectors?

[T-Bird]

Yes.. but I’ll check again today. Now I used a 12v test light during my testing of each one. Not my volt meter. This thang is whooping my ass. TU 

[T-Bird]

I went ahead and checked the fuses again. 
test light to each injector, all lit up like a Christmas tree. Unhooked the MAF sensor, tried without it plugged in, and nothing. 
electrical cleaner, plugged back in, nothing

same with the MAP sensor. Rechecked the new crankshaft and camshaft sensors electrical connections. Nothing. But again, I can put some gas in the throttle body and crank it up. I’m still convinced it’s a fuel issue due to that.. I’m lost, guys. 

[CamGTP]

To me something is telling the injectors not to fire if it runs off starting fluid or gas dumped down the throttle body. The injectors have power but the computer is stopping the injectors from firing.

 

I'm at a loss without me there and a scan tool hooked up the truck. If you can't figure it out you may need to tow it somewhere to have them look at it.

[richard wysong]

So the PCM sends a ground signal to each injector to "fire" it when cranking or running, you can check that with a test light also or use a noid light, check that and let us know

[T-Bird]

Ok, I will check that next. I have access to a car dolly. Was hoping to figure this out, but If I can’t get this figured out soon, I’ll take it to a shop. I ran it off straight gas in the TB today again. But nothing after it burned off. 
thanks again 

[richard wysong]

what is your fuel pressure?

[T-Bird]

Ok, I will check that next. I have access to a car dolly. Was hoping to figure this out, but If I can’t get this figured out soon, I’ll take it to a shop. I ran it off straight gas in the TB today again. But nothing after it burned off. 
thanks again 

[T-Bird]

The fuel pressure at the rail is 55 psi with the key turned on. I left it pressured up for 5 mins just to make sure it wasn’t bleeding down. It held the same pressure. 

[T-Bird]

Just an update. Truck still not running. 
There’s a tank pressure sensor on top of the gas tank. This truck has no external fuel filter or fuel pressure regulator. Might test the tank pressure sensor tomorrow. Running out of options. Thanks.