Please help!! LS won't start...

[EXQZME]

I stopped using the LS for about 4 days while I changed the VCG. Mostly waited for parts delivery. Today I finished the VCG and when I tried to fire her up, nothing!
It just cranks but won't fire up.

There is spark, I can hear fuel pump engage and fuel system gets pressurized every time I turn ignition on. (Half Tank still in it)
I have checked fuses they all work fine.

PATS system is not being triggered. At least I don't think so. Security light turns on for about a second or two when turning to ON. I think that is normal.

Anyhow I'm completely lost and super frustrated right now ... car was running fine before I decided to replace the vcg.

2004 LS 6 AT

What do you guys think is going on?

 

[joegr]

Can you smell raw gasoline?
Did you double check all the intake connections?

If you don't smell gas, then you could try unplugging (electrical connector) the MAF and see if it will start. If it does, you probably have a big air leak somewhere.
How do you know the fuel system is pressurizing? You could try squirting some starting spray in the intake while cranking to see if it fires up at all.

 

[EXQZME]

Yea, I double checked all connections, yes I can smell the raw gas. I tried unplugging maf, no difference.
I was cranking it and I stepped on throttle and it almost fired up but died. About the system being pressurized, I checked what I think is a purge valve in the fuel rail, when I press it in, gas squirts out.

 

[05LSV8GUY]

Yeah My car started freaking out after it sat, and lost power, and the pats disabled the starter completely so if it cranks, your right i doubt its that. You could try locking and unlocking the car, again just for kicks.

 

[joegr]

Okay, it's flooded. Hold the gas pedal all the way down, then turn the key to start (continue to hold the pedal all the way down until it is running). That should clear out the flood.
Did you let any oil drain into the cylinders (through the spark plug holes) while changing out the gaskets?

(In general, if you smell raw gas, unplugging the MAF isn't likely to help.)

 

[EXQZME]

Omg joegr!! I f****** love you man (no homo) lol.
I held throttle and cranked it like you said and the sob fired up in about 3 seconds.
Thank you so much man, you saved my life.

 

[EXQZME]

I don't how I missed that but then again I'm not sure on how it would get flooded in the first place. Thanks again though.

 

[05LSV8GUY]

unplugging the MAF isn't likely to help.

In theory wouldnt unplugging the MAF make a flood worse, since the ECM should go into default fuel trim mode. I know the comp has default fuel trims, and adjusts them off of the sensors. I just dont know if it still waits till a determined set of parameters are met, Like On older systems i know the vehicle would start with the default trim, and wouldnt start adjusting fuel trims until the O2 sensors were up to full temp only using the temp sensor to determine if it was a cold start or not.

 

[joegr]

In theory wouldnt unplugging the MAF make a flood worse,...

Yes, I believe that it might. In my defense, I did say not to do it if he could smell gasoline.

My experience is that with a very dirty or defective MAF or a major air leak, the PCM will turn off all or most fuel because it thinks the engine isn't getting any air. In these limited cases, unplugging the MAF (causing a failure effects management strategy to be used), can enable you to start the engine.