2006 cranks no start

[OCM1]

Hi,
I have a 2006 ext with the 5.3l. I recently did new lifters for the AFM system and it has been running great.
However, yesterday it stalled and now will
Not start. At time when cranking it will fire then stall out. I tried starter fluid into throttle
Body with no affect.
I have checked
No DTC set
Fuel pressure is at 53psi
It would when cranked over continue to crank when key released. I replaced the ign switch. That solved that.
I am leaning towards the crankshaft sensor

any thoughts??

 

[MBS1994]

Hi,
I have a 2006 ext with the 5.3l. I recently did new lifters for the AFM system and it has been running great.
However, yesterday it stalled and now will
Not start. At time when cranking it will fire then stall out. I tried starter fluid into throttle
Body with no affect.
I have checked
No DTC set
Fuel pressure is at 53psi
It would when cranked over continue to crank when key released. I replaced the ign switch. That solved that.
I am leaning towards the crankshaft sensor

any thoughts??

Odd timing but I just checked on my fuel pressure and I had 58. Also a 06 5.3 but mines a swb and I'd assume we both have the lh6

 

[Mooseman]

So obviously something is preventing spark. Did you check all the fuses? What about power and ground at the coils? Is there spark?

Crank sensor is a possibility. Maybe the connector worked itself loose. If you have a scope or means of checking the signal from the sensor, I'd check it first as replacing it would require a CASE relearn (but won't prevent it from running).

We have this thread from the 4.2 FAQ but most of the principles will also apply to the 5.3.
Cranks but won't start

 

[gmcman]

Will it stay running if you hold the key on "Start"

Not advised for long term use but a second or 2 won't hurt.

 

[OCM1]

Will it stay running if you hold the key on "Start"

Not advised for long term use but a second or 2 won't hurt.

Hi
I checked all fuses but darkness prevented power check. I’ll do that tomorrow
No holding the key in start will not let it keep running.
Thanks guys

 

[gmcman]

Also check that your oil pressure switch is not disconnected.

 

[OCM1]

Thanks !!
That’s a good one. I’ll look in the morning.