Cranks then dies

[Chapman_ls]

Hey fellas I need a little help on my 04 LS v8. Today i was on my way to work and i got about 20 mins from home going about 70 mph and my car lost power. No warning lights or anything. I couldn't accelerate so i coasted to the emergency lane where it died. Tried to crank it, and it started then immediately died. Got it towed and when i got off work I tried again and it still does the same thing. i checked the battery and i have 11.35 volts on Duralast Battery. I did see the battery light illuminated when in it died. I haven't checked the alternator yet but just trying to get a little advice before i dive into it this weekend. Thanks in advance

 

[joegr]

Hey fellas I need a little help on my 04 LS v8. Today i was on my way to work and i got about 20 mins from home going about 70 mph and my car lost power. No warning lights or anything. I couldn't accelerate so i coasted to the emergency lane where it died. Tried to crank it, and it started then immediately died. Got it towed and when i got off work I tried again and it still does the same thing. i checked the battery and i have 11.35 volts on Duralast Battery. I did see the battery light illuminated when in it died. I haven't checked the alternator yet but just trying to get a little advice before i dive into it this weekend. Thanks in advance

Unplug the electrical connector to your MAF sensor. If that allows it to run then either:
1. You have bug stuck on the MAF wire, check your filter and the plumbing to it.
2. Your MAF has failed.
3. You have a large air leak somewhere past the MAF.

 

[04_Sport_LS]

.

 

[Chapman_ls]

Unplug the electrical connector to your MAF sensor. If that allows it to run then either:
1. You have bug stuck on the MAF wire, check your filter and the plumbing to it.
2. Your MAF has failed.
3. You have a large air leak somewhere past the MAF.

Joegr you are the man!! I replaced the mass air flow sensor and it started and stayed running. About to take for a test drive in few. Will update soon! Thanks Again!!!

 

[MIKEBEBE]

Hey fellas I need a little help on my 04 LS v8. Today i was on my way to work and i got about 20 mins from home going about 70 mph and my car lost power. No warning lights or anything. I couldn't accelerate so i coasted to the emergency lane where it died. Tried to crank it, and it started then immediately died. Got it towed and when i got off work I tried again and it still does the same thing. i checked the battery and i have 11.35 volts on Duralast Battery. I did see the battery light illuminated when in it died. I haven't checked the alternator yet but just trying to get a little advice before i dive into it this weekend. Thanks in advance

sounds like EGR valve to me

 

[joegr]

sounds like EGR valve to me

Did you read the rest of the thread? It was the MAF. If it were a stuck open EGR valve, he could keep it running by pressing a little on the gas pedal.

The MAF was not reading the airflow, but was not so bad as to be clearly defective to the PCM. The PCM used defaults to supply fuel while starting the car. Once started it switched to normal fuel control. It read little to no airflow, so it injected little to no fuel, so the engine stalled immediately.
Starting but stalling immediately is often a symptom of a MAF problem.

 

[MIKEBEBE]

Did you read the rest of the thread? It was the MAF. If it were a stuck open EGR valve, he could keep it running by pressing a little on the gas pedal.

The MAF was not reading the airflow, but was not so bad as to be clearly defective to the PCM. The PCM used defaults to supply fuel while starting the car. Once started it switched to normal fuel control. It read little to no airflow, so it injected little to no fuel, so the engine stalled immediately.
Starting but stalling immediately is often a symptom of a MAF problem.

I heard that man. What about intermittent high voltage read on fuel pressure regulator. Any experience with that one?

 

[joegr]

I heard that man. What about intermittent high voltage read on fuel pressure regulator. Any experience with that one?

Can you give more detail on that, especially since the LS does not have a fuel pressure regulator?

 

[MIKEBEBE]

Can you give more detail on that, especially since the LS does not have a fuel pressure regulator?

yeah man the sensor on the fuel rail that's the one

 

[04_Sport_LS]

I think you are confusing the fuel pressure SENSOR, for the non existent fuel pressure regulator.

 

[Chapman_ls]

Joegr you are the man!! I replaced the mass air flow sensor and it started and stayed running. About to take for a test drive in few. Will update soon! Thanks Again!!!

hey Joegr, its been driving good every since the part change! Thanks again!

 

[MIKEBEBE]

yeah man the sensor on the fuel rail that's the one

Oh fuel rail pressure sensor high input PO193 happens only on fast deceleration that's the one whadda u think?

 

[joegr]

Oh fuel rail pressure sensor high input PO193 happens only on fast deceleration that's the one whadda u think?

First to check would be the connector at the sensor and the connector at the PCM, next would be all the wiring in between. Also be sure to verify the ground strap from the engine to the body.